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What is virtual SMP? The VMware Virtual Symmetric Multi-Processing (SMP) product allows virtual infrastructure administrators to construct virtual machines with multiple virtual processors 2 ) Define virtualization ? Virtualization is the process of implementing multiple operating systems on the same set of physical hardware to better utilize the hardware. The process of virtualization involves a virtualization layer called a hypervisor that separates the physical Hardware from the virtual machines. This hypervisor manages the virtual machines’ access to the underlying hardware components. 3 ) H/ W initiator and s/W initiator ? H/ W initiator will initiate the authentication mechanism to the storage processor without the intervention of OS. S/W inititator will initiate the connectivity with the help of OS. Its also the software which does this. Where as in H/W initiator there should be a physical card to initiate the process. Hardware initiator A hardware device referred to as an iSCSI host bus adapter (HBA) that resides in an ESX Server host and initiates storage communication to the storage processor (SP) of the iSCSI storage device. Software initiator A software-based storage driver initiator that does not require specific hardware and transmits over standard, supported Ethernet adapters. 4 ) Main difference between ESX 2.X & 3.X? 5) what are VLANS? Virtual LAN (vLAN) A logical LAN configured on a virtual or physical switch that provides efficient traffic segmentation, security, and efficient bandwidth utilization by providing traffic only to the ports configured for a respective vLAN. Trunk port (trunking) A trunk port on a switch is a port that listens for and knows how to pass traffic for all vLANs configured on the switch. NIC team The aggregation of physical ports to form a single logical communication channel. vmxnet adapter A virtualized network adapter operating inside a guest operating system. The vmxnet adapter is a high-performance virtual network adapter that operates only if VMware Tools have been installed. The vmxnet adapter is identified as ‘‘flexible’’ in the virtual machine properties. vlance adapter A virtualized network adapter operating inside a guest operating system. The vlance adapter is the default adapter used until the VMware Tools installation has been completed. e1000 adapter A virtualized network adapter that emulates the Intel e1000 network adapter. The e1000 network adapter is most common in 64-bit virtual machines. 6) what is TOE ? An ESX Server host can initiate communication with an iSCSI storage device by using a hardware device with dedicated iSCSI technology built into the device, or by using a software-based initiator that utilizes standard Ethernet hardware and is managed like normal network communication. Using a dedicated iSCSI HBA that understands the TCP/IP stack and the iSCSI communication protocol provides an advantage over software initiation. Hardware initiation eliminates some processing overhead in the Service Console and VMkernel by offloading the TCP/IP stack to the hardware device. This technology is often referred to as the TCP/IP Offload Engine (TOE). When you use an iSCSI HBA for hardware initiation, the VMkernel needs only the drivers for the HBA and the rest is handled by the device. 7 ) 802.3 tagged and untagged? 8) What is teaming? Explain the types? NIC teaming requires that all uplinks be connected to physical switches that belong to the same broadcast domain. Virtual Switch to Physical Switch To eliminate a single point of failure, the physical network adapters in NIC teams set to use the vSwitch port-based or source MAC-based load-balancing policies can be connected to different physical switches; however, the physical switches must belong to the same Layer 2 broadcast domain. Link aggregation using 802.3ad teaming is not supported with either of these load-balancing policies. 9 ) LUN Masking ? In addition to configuring zoning at the fibre channel switches, LUNs must be presented, or not presented, to an ESX Server. This process of LUN masking, or hiding LUNs from a fibre channel node, is another means of ensuring that a server does not have access to a LUN. As the name implies, this is done at the LUN level inside the storage device and not on the fibre channel switch. More specifically, the storage processor (SP) on the storage device allows for LUNs to be made visible or invisible to the fibre channel nodes that are available based on the zoning configuration. The hosts with LUNs that have been masked are not allowed to store or retrieve data from those LUNs. Zoning provides security at a higher, more global level, whereas LUN masking is a more granular approach to LUN security and access control. The zoning and LUN masking strategies of your fiber channel network will have a significant impact on the functionality of your virtual infrastructure. 10 ) What is iSCSI? iSCSI Network Storage As a response to the needs of not-so-deep-pocketed network administrators, Internet Small Computer Systems Interface (iSCSI) has become a strong alternative to fibre channel. The popularity of iSCSI storage, which offers both lower cost and increasing speeds, will continue to grow as it finds its place in virtualized networks. Understanding iSCSI Storage Networks iSCSI storage provides a block-level transfer of data using the SCSI communication protocol over a standard TCP/IP network. By using block-level transfer, as in a fibre channel solution, the storage device looks like a local device to the requesting host. With proper planning, an iSCSI SAN can perform nearly as well as a fibre channel SAN — or better. This depends on other factors, but we can dive into those in a moment. And before we make that dive into the configuration of iSCSI with ESX, let’s first take a look at the components involved in an iSCSI SAN. Despite the fact that the goals and overall architecture of iSCSI are similar to fibre channel, when you dig into the configuration details, the communication architecture, and individual components of iSCSI, the differences are profound. The components that make up an iSCSI SAN architecture, shown in Figure 4.19, include: Storage device The physical device that houses the disk subsystem upon which LUNs are built. Logical unit number (LUN) A logical configuration of disk space created from one or more underlying physical disks. LUNs are most commonly created on multiple disks in a RAID configuration appropriate for the disk usage. Storage processor (SP) A communication device in the storage device that receives storage requests from storage area network nodes. Challenge Handshake Authentication Protocol (CHAP) An authentication protocol used by the iSCSI initiator and target that involves validating a single set of credentials provided by any of the connecting ESX Server hosts. Ethernet switches Standard hardware devices used for managing the flow of traffic between ESX Server nodes and the storage device. iSCSI qualified name (IQN) The full name of an iSCSI node in the format of iqn.- .com.domain:alias. For example, iqn.1998-08.com.vmware:silo1-1 represents the registration of vmware.com on the Internet in August (08) of 1998. Nodes on an iSCSI deployment will have default IQNs that can be changed. However, changing an IQN requires a reboot of the ESX Server host. 12 ) SAN vs NAS? 14) Explain the features of ESX 3.5? 15) Ballooning? 16) What is NUMA? Non Uniform memory architecture. 17) Explain resource pools? 18) CPU Affinity advantages and disadvantages? 19 ) Limitations of Virtualization? 20 ) what are the advantages of VMfs-3? Cluster filesystems and the main advantage is its flat file system there will be no file descriptor in the filesystem which will reduce overhead to the processor. This is why the file system is high in performance. 21) Why is a LUN locked? Whenever the data is written to the LUNs during the metadata update the LUN will be locked few milli seconds so that the other ESX servers will be able to access them at that particular time. 22) What is metadata? Data about data is called as metadata. A VMFS volume contains a metadata area to manage all the files that live in the VMFS, as well as the attributes of the VMFS volume. The metadata file includes the VMFS label, number of files in the VMFS, attributes about the files, and file locks. Creating, deleting, and modifying the size of a file or its attributes updates the metadata. Because the VMFS is a cluster (distributed) file system, any update to the metadata requires locking the LUN on which the VMFS resides using a SCSI-2 Reservation. ESX uses the lock to synchronize data across all the ESX nodes accessing the VMFS. 23) What is metadata update? 24 ) what are the file extensions of VMs? A) Vmdk , vmx , log , REDO ,NVRAM, VMns 25) Command used to mount vmfs volumes? Vdf , fdisk 26) What is a sparse disk? 27) Default Ethernet device on ESX 2.5.x? A) eth0 28) Why do VMs run ; even if the service console is crash on ESX 3.5? 29 ) what is NMI ? Non maskable Interrupt 30 ) What is the use of RDM? Raw Device Mappings (RDMs) A raw device mapping (RDM) is not direct access to a LUN, nor is it a normal virtual hard disk file. An RDM is a blend between the two. When adding a new disk to a virtual machine, as you will soon see, the Add Hardware Wizard presents the Raw Device Mappings as an option on the Select a Disk page. This page defines the RDM as having the ability to give a virtual machine direct access to the SAN, thereby allowing SAN management. I know this seems like a contradiction to the opening statement of this sidebar; however, we’re getting to the part that oddly enough makes both statements true. By selecting an RDM for a new disk, you’re forced to select a compatibility mode for the RDM. An RDM can be configured in either Physical Compatibilitymode or Virtual Compatibilitymode. The Physical Compatibility mode option allows the virtual machine to have direct raw LUN access. The Virtual Compatibility mode, however, is the hybrid configuration that allows raw LUN access but only through a VMDKfile acting as a proxy. The image shown here details the architecture of using an RDM in Virtual Compatibility mode: So why choose one over the other if both are ultimately providing raw LUN access? Since the RDM in Virtual Compatibility mode uses a VMDK proxy file, it offers the advantage of allowing snapshots to be taken. By using the Virtual Compatibility mode, you will gain the ability to use snapshots on top of the raw LUN access in addition to any SAN-level snapshot or mirroring software. Or, of course, in the absence of SAN-level software, the VMware snapshot feature can certainly be a valuable tool. The decision to use Physical Compatibility or Virtual Compatibility is predicated solely on the opportunity and/or need to use VMware snapshot technology. 31 ) what is SCSI pass thru? Similar to RDMs in physical mode, SCSI pass thru mode allows a VM direct access to any SCSI device attached to the ESX Server. The main use is to gain access to a tape device. For this to happen, the SCSI host adapter is assigned to the VM for ESX versions earlier than version 3. Tape devices are only supported using Adaptec SCSI host adapters. Fibre Channel tape devices are accessible through Fibre Channel switches and are presented like any LUN. 32 ) what is SCSI-2 reservation ? SCSI Reservation is the name for the SCSI-2 locking that occurs within ESX whenever modification of the VMFS metadata occurs. The metadata of the VMFS holds the properties of all the files on the file system, including that for each file the name, size, access, and modification times, permissions, owner, and group names. A SCSI Reservation occurs whenever there is a request to update the metadata of a VMFS with new information or modification of old information. These reservations will lock the entire LUN, and although the standard states that a SCSI-2 Reservation can lock an extent or partition, it is important to realize that in ESX it requests a lock of the entire LUN. Because multiple machines can update the metadata per LUN at any time, these reservation requests can occur quite often and at the same time (and thus the possibility of SCSI Reservation conflicts occurs). Each reservation request that occurs will, once accepted, take anywhere from 1 millisecond to 12 milliseconds to complete, with an average of 7 milliseconds. Some operations take only 1 to 2 milliseconds from SCSI Reservation request, acceptance, and release. These fast operations are generally ones that change permissions, access and modification times, owner, and group names. All other operations generally lock the LUN for 7 milliseconds. Operation changes are often the only ways to alleviate a SCSI Reservation conflict. To do so, it is best to understand what can cause them. Because SCSI Reservations are issued only for those items that modify the metadata of the VMFS, there is a definitive list of operations that can cause these. 33) why do you check SCSI-queue length? A) Through ESXTOP command then press d to view disk statics. 34) How will you check the performance of the ESX ? Using TOP for CPU, free, vmstat and esxtop 35 ) what information is saved in redo log? The longer a VM is in REDO mode, the larger this increments file becomes. Undoable VMs are always in REDO mode for the life of the VM. Monitor the size of REDO files created for each VMDK backup. 36) What log is generated when vm-support command is run? 37) After installation of ESX server , root is not able to login ? why ? It’s the default setting of the ESX installation. Standard is to deny access to root to prevent unauthorized access to the system. 38 ) what is ps –auwwwx? Display all the running processes with path extension. 39 ) What is MAX Lun Count? 40 ) TCP / IP Ports 902 & 903? 41 ) what is VMKernel & Service Console? 42 ) Why should I put similar type of OS in same ESX? 43 ) difference between HBA and NIC? 44 ) What type of NIC cards are supported on ESX 3.X? 45 ) How will you check the storage paths? Esxcfg-mpath –l 46 ) What is the use of HA? 47 ) where are the configuration files stored ? What are they? 48 ) where are network setting stored ? /etc/sysconfig/networking/ 49 ) Is ESX a linux OS? NO, its not a pure linux OS. But the ESX is built with the RHEL . 51 ) Explain VMFS and why it differs from other file systems? VMFS is a simple, efficient, distributed file system that is used by the VMkernel to enable high-performance access to large files such as virtual disks for VMs with very low overhead. VMFS is the native file system in ESX, which enables the VMkernel to perform read/writes as efficiently as performing operations on a raw disk, with fast data structures used exclusively by the VMkernel, whether the VMFS is located on a local server or remote storage. VMFS is the only file system that can host VMDKs for ESX versions earlier than version 3. ESX version 3 can host monolithic VMDKs on a VMFS and multiple file VMDKs on NFS. Versions of ESX earlier than version 3 used either VMFS-1 or VMFS-2 depending on the build level. VMFS-1 and VMFS-2 are flat block file systems that did not permit a directory structure hierarchy for the reason of maintaining fast access to virtual disk files from the VMkernel. ESX version 3 introduces VMFS-3, which adds a directory structure allowing for the storage of VM configuration, disk, and swap files in one place. A single LUN may only house exactly one VMFS, which in turn will provide a container for many VM disk files from many ESX Servers if the VMFS is located on shared or local storage. The VMkernel organizes access to the VMFS by using SCSI-2 Reservation on the entire volume or LUN. Flat filesystem, No additional VMFS contains a header of the VMware file system metadata that includes all the attributes for the VMFS volume and holds the files within the volume. When a metadata update is required, the VMkernel of the ESX Server places a nonpersistent SCSI-2 Reservation on the complete VMFS volume, which creates a lock until the operation is completed. This is essential to keep other ESX Servers accessing the same VMFS volume from updating the metadata while another update is happening, which prevents metadata corruption, which is necessary for any clustered file system. The VMFS metadata attributes include the size, type, and extents of the VMFS, and information about each file. The file attributes within the metadata are a files types, permissions, ownerships, access and modification times, sizes, names, locations within the VMFS, or if a raw disk map (RDM), a direct pointer to the LUN location. After the metadata are the actual files and directories within the VMFS. 52) vmware heartbeat port number ? A. 902 53. License server port number? A. 27000 54. Advantages of vcb? LAN freeback 55. What is watchdog? 56. What are virtual resources? How many are they? The resources which can be virtualized are called virtual resources. Right now we have four types of virtual resources. CPU Memory Disk (I/O) Network. 57. What are modes of virtual switch? 58. vmkpcidivy? 59. What are virtual rdms? 60. What is virtual hardware and its upgrade? With the multiple versions of VMware ESX Server, there have been subtle but not great changes in the virtual hardware. Some aspects have been made easier to manage, but there is not a lot of difference between what virtual hardware is in use and actually how the physical hardware is used; in some cases, the virtual hardware is emulated, para virtualized, or fully virtualized in the physical CPUs (pCPUs) of the server in use. There has been quite a bit of talk about which of these concepts are the best, and until now they were not strictly necessary to understand. Emulation Para virtualization Fully virtualized 61. What are disk shares? Why are they used? Disk shares are the reservation applied to the disk so that it will be having a priority based on the access. 62. Benefits of resource pools? To guarantee the resource to the particular pool. 63. What value will you check if there is a resource problem? 64. I prefer guest OS backup rather than VCB? 65. When will vmware restarts vm automatically? If the ESX host is rebooted manually or its isolated from the network. 66. Storage array types, active/active & active passive? 67. Max no of lun iSCSI can see? Hopefully 256 68. Max no of vmfs3 volumes /esx? 69. Max no of targets for iscsi? 70. Explain load balancing policy? 71. What is 802.1Q? If adding more networks for use by the VMs, either use 802.1q VLAN tagging to run over the existing pair of NICs associated with the VMs or add a new pair of NICs for the VMs 72. Explain memory tax? Memory tax. 73. What is vmmemctrl (ballon driver)? 74. Why should we use reservation? 75. Attributes of resource pool? 76. How many host failure can a esx support? 77. Memory used by esx? 78. What is memory overhead? 79. Layers in esx server? Virtualization Layer Hardware layer User interface layer 80. What is cpu limit? 81. Define virtualization, hardware and layer? 82. What is cpu virtualization? 83. How is memory allocated to vms? Memory allocated to the VM from the ESX may be contiguous or may not be contiguous. 84. What is memory virtualization? The physical memory is assigned to a VM. If the memory is not active then the memory is reclaimed by the ESX host. If the VM is requesting additional memory then the ESX will allocate the memory overhead. This is something called memory virtulization. 85. What is vmm? Virtual Machine Manager 86. Why should I choose boot from san? You don’t want to manage the storage locally. 87. What are the esx server management process and services run in service console? Vmware-hostd Vmware-server Vpxa Watchdog 88. Why multi pathing is used to transfer the data from host to san? In case of a path failure the host can access the other path. 89. Minimum hardware requirements for esx? 90. Which OS is supported for vc? Windows XP SP2 , Windows 2003, 91. Databases supported for vc? Oracle 8i not sure , Microsoft SQL 2000 update 4. 92. Types of scsi controllers for vms? 93. How will you implement a scsi target? types? 94. Is MSCS (Microsoft clustering) is supported under vm? 95. Polls defined in virtual center? 96. What is transparent page sharing? Is used to eliminate redundant pages from the memory. 97. Can I install multi-pathing software in vm? No, you can’t because the host itself will have multi-pathing software. No, Multipathing software is used at the host level itself. Hence it’s not required to install multi-pathing software. 98. Requirement to allow nic teaming? There should be atleast two NIC to do the teaming. And the NIC should be compactable with the teaming software. 99. Minimum ram required for vmware converter? A ) 128 100. vswitch policies? 101. What is file level access and block level access? File level access is done through the TCP/IP protocol where there will be a file descriptor to access the file. Ex: NAS. Block level access is done through FC protocol where the data is accessed in chunks. This is faster than file level. Ex: SAN 102. How to shutdown or restart a vm from service console? Soft Hard Through vmware-cmd command. 103. What is uuid? Unique user identifier. 104. How will you know whether the esx is restarted manually or not? First check the dmesg and logs. Check the history of the command whether any reboot command or inet 6 or shutdown command is issued. Check the IML logs and HP SIM page. 105. ESX host becomes unresponsive during boot after the message: enabling interupts? Need to check HCL ( hardware compatibility list ). There would be problem with IRQs. 106. How is virtualization like a dual-boot system? A: It is nothing like a dual-boot system. A dual-boot system still runs only one OS at a time, has no idealized hardware environment, and provides no encapsulation or portability. 107 Q: What do you mean virtual machines are portable? A: Because virtual machines are encapsulated in their .vmdk files and VMware provides an idealized hardware environment, virtual machines can be moved from one ESX Server to the next either using Vmotion or importing the .vmdks. 108: How is VMware more stable than, say, a new physical server? A: The idealized hardware provided by VMware provides a consistent virtual hardware environment that increases that stability of your virtual machines independent of the underlying physical hardware. 109: Is any installation method better than any other? A: No. Whichever installation method you're comfortable with and that produces a good build is the one for you. 110: I'm having problems with my installation. What should I do? A: Ensure that the hardware you're loading ESX Server on is supported. The same goes for the configuration. If you are certain the hardware and configuration are supported, then run the vm-support script mentioned previously. 111: Why does this chapter include only the graphical installer method? A: It's the recommended installation method from VMware and one that many in the x86-world are the most comfortable with. If you wish to try it another way, VMware offers a very complete installation document covering the various installation methodologies. 112. When I copy my virtual machine and try to run it on my network, I get hostname already exists and IP address already exists errors. I thought I could simply copy my virtual machine. What is the problem? A: You can copy your virtual machine, which is why you're running into this problem. The copy is an exact copy. Thus, you need to change the hostname, IP address, and even the computer's SID (if it has one). 113: Can I move my Gold Master to my other ESX Servers? A: Yes, it's a recommended time-saver. If your ESX Servers share a LUN, that too is a way to access your Gold Master or your VMlibrary for that matter. 114: Are there any limitations to the number of virtual machines I can run on my ESX Server? A: Yes. Each ESX Server allows for only 80 virtual CPUs and 200 registered virtual machines. 115: Can I take a virtual machine running on VMware Workstation or GSX and run it in ESX? A: It depends. The process is not as simple as cutting and pasting. There is a specific import process required for migrating virtual machines from either Workstation or GSX into ESX. Access the following link for the exact instructions: http://www.vmware.com/pdf/mobility_guide.pdf. Q: Do you need to tweak the settings of your virtual machines after you've built them? A: No. VMware has configured the defaults of your build to suit most server loads. However, depending on the profile of your server and the resource intensiveness of the service it's providing, you may want to consider tweaking some of the default settings to better ensure service stability and reliability. Q: Are there more advanced features than the ones detailed in this chapter? A: Yes… a lot more. Q: Is clustering more stable in VMware? A: We find that the idealized hardware, in combination with VMware's improvements in clustering support, has made virtual clustering very stable. Q: Can you Vmotion a cluster? A: That depends on the cluster type and how it is configured. Clusters using Raw Device Mapping in virtual mode can be moved with Vmotion according to VMware documentation. Q: Does VMware support NIC teaming? A: Yes, and it's a very good idea to configure your ESX Server, especially if it's for production, with teamed NICs. This will provide hardware fault tolerance in case one NIC fails. Q: How many physical NICs do I need on my ESX Server? A: That depends on the number of virtual machines and the network traffic they produce. You should have a minimum of two: one for your Service Console and one dedicated to your virtual machines. Q: If I'm building a cluster using Microsoft Clustering Service, what's the best configuration for my heartbeat NIC? A:For a Cluster in a Box, create a VMnet that your nodes of your cluster can attach their heartbeat NICs. Q: Can you attach virtual machines on any ESX Server to a VMnet? A: No. Only virtual machines on the ESX Server that the VMnet resides can attach to it. Q: Why should you pay for a p-to-v toll when there are a number of ways to do it for free? A: If you don't have the time or inclination to learn the manual process or need the assurance of a vendor for your physical-to-virtual migrations, then a tool that comes with support is a very reasonable option. Q: What takes the longest in the p-to-v process? A: Transferring the data of the physical server into either an image file or the virtual server itself. That's why tweaking your network settings for optimal throughput is essential when p-to-v'ing a server. Q: Can you create complete backups of your physical servers and then recover them into virtuals? A: I've used NTBackup to back up Windows 2000 Professional and Windows XP, and created virtuals out of .bkf files. It works but there's a bit of futzing around with the virtual once it is running. Try it. Q: What's the most essential part of creating a smooth migration plan? A: Practice. No matter what the tool or process, practice it and learn its gotchas and the workarounds. No matter what method you use, there will be times when it won't go as planned. Practicing your p-to-v process on a number of physical platforms and disk configurations allows you to become more adept once you're doing it for real. Q: Will my software vendor support my application in a VMware environment? A: You'll need to contact your specific software or applications vendor to find out; however, an increasing number of software vendors support virtualized environments. Once you've migrated your application from a physical to virtual environment it's very easy to migrate back to a physical environment for vendor support. An excellent document provided by VMware can be found at the following link: www.vmware.com/pdf/ms_support_statement.pdf. Q: What are the best enablers to help ensure our server consolidation is a success? A: Engaging with the lines of business and application owners not only assists in attaining an actionable schedule, but also develops a highly collaborative environment that facilitates buy-in and support for your project. In addition it will be difficult to incorporate rationalization into your project unless you are working directly with the business or application owners. Q: What tools do you recommend for a server consolidation or virtualization project? A: It's imperative to have a robust and comprehensive tool for capacity planning, including historical data. This tool can be utilized in every phase of your project. Other tools to support the project include modeling tools used in test consolidation scenarios. Finally, you'll need to evaluate and document tools and processes for each technology you wish to consolidate. The migration tools will need to support all the platforms you wish to use in your migration scenarios. Q: What is the VMlibrary? A: The VMlibrary (/vmlib) is simply a directory on your ESX Server that lets you organize the tools and files you need to manage and maintain your virtual infrastructure, Q: Can ISOs be shared between ESX Servers? A: If you place your VMlibrary on a LUN that's shared amongst your ESX Servers, you can share your ISO images or anything else you place in your VMlibrary. Q: Why is Vmotion so cool? A: Try it…and then imagine the possibilities and applications. You'll be a convert soon enough. Q: You mentioned that additional ISVs were creating management capabilities for virtual infrastructures in their products. Which ones? A: Look at HP Insight Manager, Dell OpenManage, IBM Director, BMC's Patrol product line, Computer Associates' Unicenter, and many others. Q: I can't add a new virtual hard drive to my virtual machine. What should I do? A: You may not have the appropriate permissions to add virtual hardware to the VM, or the VM may be powered on and won't allow the addition of virtual hardware while powered on. Q: I just created a new virtual machine and attached to an existing disk. Every time I power on the VM, I get a blue screen. What could the problem be? A: Make sure the OS type that you selected when you created the VM matches the OS type installed on the virtual disk. For example, if you selected Windows 2003 Standard for the VM when you created it, but the existing virtual disk has Windows 2000 Standard installed, you'll probably encounter issues. Q: I followed the directions for Active Directory authentication, and I still can't log in using an account and password in AD. What should I do? A: Check the time on your ESX Server and Active Directory and make sure they're synced up. Kerberos is very sensitive to being out of sync and could reject credentials if the time is not within specific limits. You can also review the System event logs for clues. Q: What is the most important aspect of deploying ESX Server and virtual machines? A: The ability to provide service at least as good as that which you had with physical servers. With adherence to best practices, you should easily be able to provide this and exceed it by a phenomenal degree. Q: ISOs have been mentioned in several of the chapters. Why are they so important? A: Good administrators strive to never leave their chairs, cubes, or offices. If they do, they may just run into a user (we're kidding, of course). Having a library of ISOs can help you in this endeavor. In addition, they run a lot faster than regular CDs. Q: What will happen if I deploy systems management software on the ESX Server itself? A: If you're going to do this, make sure you allocate enough memory so that the application doesn't impact the performance of your ESX Server and thus your virtual machines. Also, use a system management package that is supported and test your installation on your ESX Server thoroughly. If you notice a degradation of performance, contact the systems management software vendor. The major vendors have instructions and best practices for deploying their products onto ESX Server. Q: What is the most important best practice to follow? A: The one that ensures your smooth evolution into a virtual infrastructureeducation. Learn every aspect of a virtual environment to the best of your ability. Be passionate about it and you'll reap the rewards. See the recommended reading list, troll the VMware Web site regularly, as well as other Web sites dedicated to virtualization such as p2v.net, vmguru.com, and virtual-strategy.com. Q: Which version of VMware ESX Server supports Boot from SAN? A: ESX Server 2.5 supports Boot from SAN but has the following limitations: ESX server had to be installed in boot from SAN mode, the HBA can only be used by the Service Console, LUN masking should be used to restrict other ESX servers from the boot LUN, the HBA of the boot LUN must be a QLogic HBA, and the boot LUN must be the lowest numbered LUN controlled by the storage processor. Q: Where are log files for VMware ESX Server written to? A: /var/logs/vmware Q: What do you do if you forget the root password of the Service Console? A: You will need to boot into single-user mode from the Service Console by selecting linux from the LILO boot menu and appending -s to your boot choice. This will boot the console into single-user mode and will allow you to use the passwd command to change the root user password. Q: Why do I still see processes for my virtual machine when running the ps command on the Service Console even though my virtual machine is powered down? A: If there is still a virtual console session running for your VM, you will still see processes associated with it for mouse, keyboard, and screen (MKS) even though it is powered off. Q: I accidently unmounted the VMFS volume on my ESX Server. How can I re-mount the volume without re-booting A: You can type mount -t vmfs vmfs /vmfs Q: What software is qualified for use with VMware 2.5.1? A: Please see http://vmware.com/pdf/esx_backup_guide.pdf for an up-to-date list of software that's compatible with ESX. Q: What SANs are compatible with ESX Server? A: Please see http://vmware.com/pdf/esx_SAN_guide.pdf for details on ESX-to-SAN server compatibility. Q: What are the certified backup tools for ESX? A: Please see http://vmware.com/support/esx25/doc/backup_tools_links.html. Q: Can I back up my entire virtual machine from the Service Console? A: Yes, but it is not advised. The console services should be left alone to manage the entire virtual machine infrastructure. It's best that backups be performed by separating the applications and data from the operating systems because backups can become quite large very quickly. You should consider a backup of the environments that change frequently (data and applications) with an agent specifically designed to perform this function. A backup of those virtual disks that change infrequently and need VMFS formats should be backed up from the Service Console. These console-based backups should be performed in a powered-down or suspended approach (preferred), or a suspended environment using redo logs as an alternative. All backups performed from a systems console mode must be restored in an all-or-nothing approach. Recovery for a single file or directory can only be accomplished via a backup agent or from a backup to a SAN environment using a variety of different recovery/restoral techniques. Q: I'm not able to connect to the Service Console over the network. What could the issue be? A: You may have allocated the Service Console NIC to the VMkernel. Use vmkpcidivyi to reassign the NIC to the Service Console. Q: I have a virtual machine that did not start up correctly, but now I can't power it down from the MUI or Virtual Center. How can I get this VM to shut down? A: You can use the vmware-cmd utility to force a hard power down. The following syntax should work: vmware-cmd /path-to-vm/vm-directory/vm.vmx stop hard Q: I find using commands to be very difficult. Why can't I use X Windows on the Service Console? A: You actually could run the X Windows system on the Service Console, but it will eat up valuable resources that are needed by the system to manage all the processes related to Virtualization. VMware specifically says not to run X Windows on the Service Console. So, it's best to just buck up and deal with it. Q: Is there a way to mount the vmfs volumes if they accidentally get unmounted without having to reboot? A: Yes. You can run mount vmfs vmfs /vmfs. Q: How do I check the speed and duplex setting of the Service Console NIC? Also, how do I change it if needed? A: You'll need to cat out the eth0.info file for your type of adapter. This file can be found at /proc/net/type-of-nic/eth0.info. To give you an example, our server has an Intel Pro 100 Nic for the Service Console, so for us to find the speed and duplex information we would type: cat /proc/net/PRO_LAN_Adapters/eth0.info. Q: How long has Xen been around? A: Since 2004, and they're located in Palo Alto, California. Hmm…what other virtualization company is in Palo Alto? Q: What is a hypervisor? A: In VMware parlance, it's the virtualization layer. Q: Why did VMware limit its beta of ESX Server 3.0 to so few? A: Good question…We don't know, and we hope that VMware's future beta programs are opened up to a larger audience. Q: If I can't get a SAN, will local storage with a RAID device be sufficient? A: Absolutely. You won't get some of the cooler tools like VMotion, but being virtual on local storage is better than remaining physical. 1) What is the most critical component in SAN? 2) What is the default id for SCSI HBA? 3) What is parallelism? 4) What do you know about SAN testing? 5) Explain a typical SAN landscape? 6) What is fan-in and fan-out in SAN Virtualization system? 7) How is the interoperability between the server and the storage is achieved? 8) What are the performance metrics of SAN? 9) What do you know about I/O meters , their types and how are the used? 10) What is the equivalent of Address resolution protocol in storage? 11) What is meant by availability & reliability in Storage ? 12) What is Disaster Recovery & how it is implemented in a Storage environment? 13) Example for failover cluster configurations ? 14) What are the needs/advantages of Storage consolidation ? 21) What is the purpose of disk array? Probability of unavailability of data stored on the disk array due to single point failure is totally eliminated. 22) What is disk array? Set of high performance storage disks that can store several terabytes of data. Single disk array can support multiple points of connection to the network. 23) What is virtualization? A technique of hiding the physical characteristics of computer resources from the way in which other system application or end user interact with those resources. Aggregation, spanning or concatenation of the combined multiple resources into larger resource pools. 24) What is Multipath I/O? Fault tolerant technique where by there is more than one physical path between the CPU in the computer systems and its main storage devices through the buses, controllers, switches and other bridge devices connecting them. 25) What is RAID? Technology that groups several physical drives in a computer into an array that you can define as one or more logical drive. Each logical drive appears to the operating system as single drive. This grouping enhances the performance of the logical drive beyond the physical capability of the drives. 26) What is stripe-unit-size? It is data distribution scheme that complements the way operating system request data. Granularity at which data is stored on one drive of the array before subsequent data is stored on the next drive of the array. Stripe unit size should be close to the size of the system I/O request. 27) What is LUN Masking? A method used to create an exclusive storage area and access control. And this can be achieved by storage device control program. 28) What is the smallest unit of information transfer in FC? Frame 29) how is the capacity of the HDD calculated? Number of Heads X Number of Cylinders X Sectors per track X Sector Size 30) what is bad block reallocation? A bad sector is remapped or reallocated to good spare block and this information is stored in the internal table on the hard disk drive. The bad blocks are identified during the media test of the HDD as well as during various types of read write operations performed during the I/O tests. Apart from the new generation of HDD comes with a technology called BGMS (background media scan) which continuously scans the HDD media for defects and maps them when the drive is idle (this is performed after the HDD is attached to the system). 31) What are tow types of recording techniques on the tapes? a) Linear Recording b) Helical Scan Recording. 32) What is snap shot? A snapshot of data object contains an image of data at a particular point of time. 33) What is HSM? Hierarchical storage management, an application that attempts to match the priority of data with the cost of storage. 34) What is hot-swapping? Devices are allowed to be removed and inserted into a system without turning off the system. 35) What is Hot-Sparing? A spare device is available to be inserted into the subsystem operation without having to remove and replace a device. 36) What are different types of backup system? a) Offline b) Online c) Near Line 37) What is the different between mirroring, Routing and multipathing? Redundancy Functions Relationships Role Mirroring Generates 2 i/os to 2 storage targets Creates 2 copies of data Routing Determined by switches independent of SCSI Recreates n/w route after a failure Multipathing Two initiator to one target Selects the LUN initiator pair to use 38) Name few types of Tape storage? a) Digital Linear Tape b) Advanced Intelligent Tape c) Linear Tape Open 39) What is a sequence in FC? Group of one or more frames that encompasses one or more “information units” of a upper layer protocol. Example: It requires i) One sequence to transfer the command ii) One or more sequence to transfer the data iii) Once sequence to transfer the status. 40) What is Exchange in FC? Exchange is to establish a relationship between 2 N_PORTs and then these two ports transfer data via one or more sequence within this relationship. Example: Exchange exist to transfer the command, data and the status of one SCSI task 40) What is Exchange in FC(Fibre Channel)? Exchange is to establish a relationship between 2 N_PORTs and then these two ports transfer data via one or more sequence within this relationship. Example: Exchange exist to transfer the command, data and the status of one SCSI task 41) Why do we need Login in FC? Port Login: To exchange service parameters between N_Ports and N_Ports Process Login: To establish the SCSI operating environment between two N_PORTS 42) What are the different types of clusters? a) High availability clusters b) High Performance Clusters c) Load Balancing Clusters. 43) What are three levels of management in storage? a) Storage Level Management b) Network Level Management c) Enterprise Level Management. 44) What are the key activities in SAN management? a) Monitoring b) Configuring c) Controlling d) Troubleshooting e) Diagnosing 45) What is the difference between HBA and NIC? HBA => Host bus adapters are used in storage based traffic while NIC (Network Interface Cards are used in IP based LAN traffic. 46) What is the measuring unit of data activity? Gigabits per hour 47) What are the basic storage policies? a) Security and authentication b) Capacity, Content and quota management c) Quality of Service 48) What is bypass circuitry? A circuit that automatically removes the storage device from the data path (FC device out of FC AL loop) when signaling is lost (this signal is called port by-pass signal). 49) Explain different classes of service in FC? Class 1: dedicated connection between two communicators with acknowledgement of frame delivery. Class 2: is connection less but provides acknowledgement Class 3: is connection less and provides no notification of delivery Class 4: allows fractional bandwidth for virtual circuits Class 5: Provides multicast with acknowledgment Class F: Is used for switch to switch communication in the fabric. 50) How many connections are possible in Fabric topology? 2^24 (24 bit address to the port) , and the largest possible fabric will have 239 interconnected switches. 51) What is one of the constrains of using storage switch? Latency 52) What is the difference between NAS and SAN? NAS Cables used in the n/w n/w protocols (TCP/IP, IPx) and file sharing protocols (IFS & NFS) Lower TCO Support heterogeneous clients Slow SAN High-speed connectivity such as FC Do not use n/w protocols because data request are not made over LAN Higher TCO Requires special s/w to provide access to heterogeneous clients Fast 53) What is Jitter? Jitter refers to any deviation in timing that a bit stream suffers as it traverses the physical medium and the circuitry on-board the end devices. A certain amount of deviation from the original signaling will occur naturally as serial bit stream propagates over fibre-optic or copper cabling. Mainly caused by electro magnetic interference 54) What is BER/Bit error rate? Probability that a transmitted bit will be erroneously received is the measure of number of bits (erroneous) at the output of the receiver and dividing by the total number of bits in transmission. 55) What is WWPN? WWPN is the 16bit character that is assigned to the port, SAN volume controller uses it to uniquely identify the fibre channel HBA that is installed in the host system. 56) What is connection allegiance? Given multiple connections are established, individual command/response pair must flow over the same connection. This connection allegiance ensures that specific read or writes commands are fulfilled without the additional overhead of monitoring multiple connections and to see whether a particular request is completed. 57) What is burst Length? The burst length is the number of bytes that the SCSI initiator sends to the SCSI target in the FCP_DATA sequence. 58) Explain different types of RAID? RAID 0: data striping blocks are written sequentially, no redundancy, high performance than single disk access. RAID 1: Mirroring, data blocks written to both disk at once, 100% redundancy, 100% additional capacity required. Read can be distributed across both the disks to increase performance. RAID 3: Striping with byte parity, adds parity information to rebuild data in the event of disk failure, high transfer rate and availability with lower capacity required than RAID 1. Transactions performance low because all disks operate in lock step. RAID 4: striping with block parity, independently accessible disks, data blocks written sequentially to each disk failure. Dedicated parity disk is write bottleneck and leads to poor performance. RAID 5: Striping with rotational parity, parity blocks written per row and distributed across all disks, parity distribution eliminates single write bottleneck overhead for parity calculation on write supplemented with parallel microprocessors or caching. 59) What is NAS in detail ? NAS or Network Attached Storage “NAS is used to refer to storage elements that connect to a network and provide file access services to computer systems. Abbreviated NAS. A NAS Storage Element consists of an interface or engine, which implements the file services, and one or more devices, on which data is stored. NAS elements may be attached to any type of network. When attached to SANs, NAS elements may be considered to be members of the SAS (SAN Attached Storage) class of storage elements. A class of systems that provide file services to host computers. A host system that uses network attached storage uses a file system device driver to access data using file access protocols such as NFS or CIFS. NAS systems interpret these commands and perform the internal file and device I/O operations necessary to execute them.” Though the NAS does speed up bulk transfers, it does not offload the LAN like a SAN does. Most storage devices cannot just plug into gigabit Ethernet and be shared - this requires a specialized file server the variety of supported devices is more limited.NAS has various protocols established for such needed features as discovery, access control, and name services. 60)Briefly list the advantages of SAN ? SANs fully exploit high-performance, highconnectivity network technologies SANs expand easily to keep pace with fast growing storage needs SANs allow any server to access any data SANs help centralize management of storage resources SANs reduce total cost of ownership (TCO) Which are the SAN topologies? Answer :SAN can be connected in 3 types which are mentioned below: Point to Point topology FC Arbitrated Loop ( FC :Fibre Channel ) Switched Fabric 2) Which are the 4 types of SAN architecture types Answer :Core-edge Full-Mesh Partial-Mesh Cascade 3) which command is used in linux to know the driver version of any hardware device ? Answer : dmesg 4) How many minimum drives are required to create R5 ( RAID 5) ? Answer : You need to have at least 3 disk drives to create R5. 5) Can you name some of the states of RAID array ? Answer : There are states of RAID arrays that represent the status of the RAID arrays which are given below online Degraded Rebuilding Failed 6) Name the features of SCSI-3 standard ? Answer : QAS: Quick arbitration and selection Domain Validation CRC: Cyclic redundancy check 7) Can we assign a hot spare to R0 (RAID 0)array? Answer :No, since R0 is not redundant array, failure of any disks results in failure of the entire array so we cannot rebuild the hot spare for the R0 array. 8) Can you name some of the available tape media types ? Answer :There are many types of tape media available to back up the data some of them are DLT :digital linear tape - technology for tape backup/archive of networks and servers; DLT technology addresses midrange to high-end tape backup requirements. LTO :linear tape open; a new standard tape format developed by HP, IBM, and Seagate. AIT :advanced intelligent tape; a helical scan technology developed by Sony for tape backup/archive of networks and servers, specifically addressing midrange to high-end backup requirements. 9) what is HA ? Answer : HA High Availability is a technology to achive failover with very less latency. Its a practical requirement of data centers these days when customers expect the servers to be running 24 hours on all 7 days around the whole 365 days a year - usually referred as 24x7x365. So to achieve this a redundant infrastructure is created to make sure if one database server or if one app server fails there is a replica Database or Appserver ready to takeover the operations. End customer never experiences any outage when there is a HA network infrastructure. 10) What is virtualization? Answer :Virtualization is logical representation of physical devices. It is the technique of managing and presenting storage devices and resources functionally, regardless of their physical layout or location.Virtualization is the pooling of physical storage from multiple network storage devices into what appears to be a single storage device that is managed from a central console. Storage virtualization is commonly used in a storage area network (SAN). The management of storage devices can be tedious and time-consuming. Storage virtualization helps the storage administrator perform the tasks of backup, archiving, and recovery more easily, and in less time, by disguising the actual complexity of the SAN. 1. What is SCSI ? What is SASI 2. What are the advantages of SCSI compared to ATA or IDE ? 3. Explain SCSI ID usage & its usage in narrow SCSI ? 4. Give SCSI Evolution ( Mention different types of SCSI ) 5. What is CDB ? 6. What are different SCSI command phases ? 7. Mention device types in SCSI-3 ? 8. What is the difference between LVD & HVD ? 8. What is the difference between SE & Differential (HVD) SCSI ? 9. What is a LUN ? 10.Mention differences between SCS-1,2 and 3 ? 11. What is a terminator? 12. What are the differences between synchronous & asynchronous SCSI ? 13. What is the default ID of SCSI HBA? 14. How you will install device drivers for HBA during OS installation? 15. What is parallel SCSI daisy chaining? 16. Explain arbitration & Selection process? 17. What are the maximum no. of devices supported in SCS-1,2 and 3 ? 18. What is the maximum length of cable supported in SCS-1,2 and 3 ? 19. What is the difference between a SCSI HBA & SCSI RAID Controller card ? 20. What is the Disk speed of different SCSI drives ? What is RAID? 2. What are the advantages of RAID? 3. What are different levels of RAID? 4. Explain RAID0, RAID1, RAID5 ? 5. What the difference between RAID0 & RAID1 ? 6. What the difference between RAID1 & RAID5 ? 7. What the difference between RAID3 & RAID5 ? 8. What the difference between RAID01 & RAID10 ? 9. How many minimum disk drives are needed for R0,R1,R5,R10,R01 ? 10. How RAID 5 works and how parity is calculated ? 11. Other than RAID features what are the other features in Software Management Functionalities ? 12. What is initialization ? 13. What is Check consistency ? 14. What is background verification ? 15. What is a RAID array? 16. What the difference between a JBOD & a RAID array? 17. When JBOD is preferred over RAID array ? 18. What is a hot spare ? 19. What is a Logical drive or Virtual drive ? 20. What is rebuilding of array ? 21. What you do when a drive in an array fails, how you bring it back to optimal online mode ? 22. What are the different states an array can be in and explain each state? 23. Explain Online ,Offline, Degraded states of an array ? 24. What is the difference between a global hotspare & a dedicated hotspare ? 25. How RAID is configured through BIOS ? 26. How RAID is configured in OS level? 27. What is the difference between a software RAID & hardware RAID ? 28. Which is best RAID level for performance and which is best for redundancy? 1. What is FC? 2. What are the advantages of FC? 3. Mention the differences between FC & SCSI? 4. Explain the layers in FC Protocol? 5. What are the functions of layer2 and layer3 in FC ? 6. What are different FC topologies? 7. What is the difference between point to point & Switched in FC ? 8. Explain FC-AL? 9. Explain the process of initialization in FC ? 10. Explain these terms : LIFA,LIPA,LIHA,LISA 11.What is a Fabric and what are its components ? 12. What are the different FC ports ? 13. Explain different types of flow controls ? 14. What is the difference between buffer to buffer and End to End flow control ? 15. What are the different classes of Services and explain them ? 16. Explain addressing in FC ? 17. Explain FC login process ? 18. What is transmission character and transmission word ? 19. What is a frame, sequence and exchange ? 20. Explain FC frame composition ? 21. Why do we need login in FC ? 22. How many connections are possible in FC ? 23. What are the maximum devices supported in each topologies of FC ? 24. What is the difference between FC & iSCSI ? 25. Mention the FC Controller card manufacturers you know ? Q: What is the minimum size for a VMFS 3 partition? A: 1200 MB Q: How many LUN’s are supported during installation? A: 128 Q: What types of external storage is supported by VMFS 3 A: Fibre Channel, iSCSI, and NAS Q: Before installing VMware ESX server 3 where should you go to get the latest media? A: www.vmware.com/download Q: What should you check before choosing a server to install A: http://www.vmware.com/pdf/vi3_systems_guide.pdf Q. Can I Update my ESX servers without any disruption to the virtual servers? A: When using VMware in conjunction with a SAN environment you can put the ESX server in Maintenance mode which will migrate the running VM’s over to another running ESX host. Q: What editions are available for VMware Converter? A: VMware converter comes in two versions, Starter Edition, and Enterprise Edition. Q: Can I use this product to make a copy of my workstation? A: Yes this product supports Windows 2000 Professional and Windows XP. Q: Can I convert a server from one hardware manufacturer to a VMware server running on a different physical server from a different hardware manufacturer? A: Yes, for example you can take a server running on Dell hardware and migrate it to a VMware server running on HP hardware. Q: Can I convert a server without making any changes to the source machine? A: Yes, VMware Converter enterprise has an option to use a boot disk on the physical server to avoid the need to install the VMware converter agent. Q: Can I shrink or extend disk sizes when migrating a machine? A: Yes, This is especially benefi cial when you have a source machine with a large amount of free space and you want to use space more effi ciently on the destination storage. 1. How we can raise domain functional & forest functional level in Windows Server 2003? 2. Which is the deafult protocol used in directory services? 3. What is IPv6? 4. What is the default domain functional level in Windows Server 2003? 5. What are the physical & logical components of ADS 6. In which domain functional level, we can rename domain name? 7. What is multimaster replication? 8. What is a site? 9. Which is the command used to remove active directory from a domain controler? 10. How we can create console, which contain schema? 11. What is trust? 12. What is the file that’s responsible for keep all Active Directory database? 13. What are the required components of Windows Server 2003 for installing Exchange 2003? - ASP.NET, SMTP, NNTP, W3SVC 14. What must be done to an AD forest before Exchange can be deployed? – Setup /forestprep 15. What Exchange process is responsible for communication with AD? DSACCESS 16. What 3 types of domain controller does Exchange access? – Normal Domain Controller, Global Catalog, Configuration Domain Controller 17. What connector type would you use to connect to the Internet, and what are the two methods of sending mail over that connector? – SMTP Connector: Forward to smart host or use DNS to route to each address 18. How would you optimise Exchange 2003 memory usage on a Windows Server 2003 server with more than 1Gb of memory?- Add /3Gb switch to boot.ini 19. What would a rise in remote queue length generally indicate? – This means mail is not being sent to other servers. This can be explained by outages or performance issues with the network or remote servers. 20. What would a rise in the Local Delivery queue generally mean? – This indicates a performance issue or outage on the local server. Reasons could be slowness in consulting AD, slowness in handing messages off to local delivery or SMTP delivery. It could also be databases being dismounted or a lack of disk space. 21. What are the standard port numbers for SMTP, POP3, IMAP4, RPC, LDAP and Global Catalog? - SMTP Ã¢â‚¬â€œ 25, POP3 Ã¢â‚¬â€œ 110, IMAP4 Ã¢â‚¬â€œ 143, RPC Ã¢â‚¬â€œ 135, LDAP Ã¢â‚¬â€œ 389, Global Catalog - 3268 22. Name the process names for the following: System Attendant? Ã¢â‚¬â€œ MAD.EXE, Information Store Ã¢â‚¬â€œ STORE.EXE, SMTP/POP/IMAP/OWA Ã¢â‚¬â€œ INETINFO.EXE 23. What is the maximum amount of databases that can be hosted on Exchange 2003 Enterprise? - 20 databases. 4 SGs x 5 DBs. 24. What are the disadvantages of circular logging? - In the event of a corrupt database, data can only be restored to the last backup. 25. Describe how the DHCP lease is obtained. It’s a four-step process consisting of (a) IP request, (b) IP offer, Ã‚Â© IP selection and (d) acknowledgement. 26. I can’t seem to access the Internet, don’t have any access to the corporate network and on ipconfig my address is 169.254.*.*. What happened? The 169.254.*.* netmask is assigned to Windows machines running 98/2000/XP if the DHCP server is not available. The name for the technology is APIPA (Automatic Private Internet Protocol Addressing). 27. We’ve installed a new Windows-based DHCP server, however, the users do not seem to be getting DHCP leases off of it. The server must be authorized first with the Active Directory. 28. How can you force the client to give up the dhcp lease if you have access to the client PC? ipconfig /release 29. What authentication options do Windows 2000 Servers have for remote clients? PAP, SPAP, CHAP, MS-CHAP and EAP. 30. What are the networking protocol options for the Windows clients if for some reason you do not want to use TCP/IP? NWLink (Novell), NetBEUI, AppleTalk (Apple). 31. What is data link layer in the OSI reference model responsible for? Data link layer is located above the physical layer, but below the network layer. Taking raw data bits and packaging them into frames. The network layer will be responsible for addressing the frames, while the physical layer is reponsible for retrieving and sending raw data bits. 32. What is binding order? The order by which the network protocols are used for client-server communications. The most frequently used protocols should be at the top. 33. How do cryptography-based keys ensure the validity of data transferred across the network? Each IP packet is assigned a checksum, so if the checksums do not match on both receiving and transmitting ends, the data was modified or corrupted. 34. Should we deploy IPSEC-based security or certificate-based security? They are really two different technologies. IPSec secures the TCP/IP communication and protects the integrity of the packets. Certificate-based security ensures the validity of authenticated clients and servers. 35. What is LMHOSTS file? It’s a file stored on a host machine that is used to resolve NetBIOS to specific IP addresses. 36. What’s the difference between forward lookup and reverse lookup in DNS? Forward lookup is name-to-address, the reverse lookup is address-to-name. 37. How can you recover a file encrypted using EFS? Use the domain recovery agent. 38. What is Active Directory? 39. What is LDAP? 40. Can you connect Active Directory to other 3rd-party Directory Services? Name a few options. 41. Where is the AD database held? What other folders are related to AD? 42. What is the SYSVOL folder? 43. Name the AD NCs and replication issues for each NC? 44. What are application partitions? When do I use them 45. How do you create a new application partition? 46. How do you view replication properties for AD partitions and DCs? 47. What is the Global Catalog? 48. How do you view all the GCs in the forest? 49. Why not make all DCs in a large forest as GCs? 50. Trying to look at the Schema, how can I do that? 51. What are the Support Tools? Why do I need them? 52. What is LDP? What is REPLMON? What is ADSIEDIT? What is NETDOM? What is REPADMIN? 53. What are sites? What are they used for? 54. What's the difference between a site link's schedule and interval? 55. What is the KCC? 56. What is the ISTG? Who has that role by default? 57. What are the requirements for installing AD on a new server? 58. What can you do to promote a server to DC if you're in a remote location with slow WAN link? 59. How can you forcibly remove AD from a server, and what do you do later? • Can I get user passwords from the AD database? 60. What tool would I use to try to grab security related packets from the wire? 61. Name some OU design considerations. 62. What is tombstone lifetime attribute? 63. What do you do to install a new Windows 2003 DC in a Windows 2000 AD? 64. What do you do to install a new Windows 2003 R2 DC in a Windows 2003 AD? 65. How would you find all users that have not logged on since last month? 66. What are the DS* commands? 67. What's the difference between LDIFDE and CSVDE? Usage considerations? 68. What are the FSMO roles? Who has them by default? What happens when each one fails? 69. What FSMO placement considerations do you know of? 70. I want to look at the RID allocation table for a DC. What do I do? 71. What's the difference between transferring a FSMO role and seizing one? Which one should you NOT seize? Why? 72. How do you configure a "stand-by operation master" for any of the roles? 73. How do you backup AD? 74. How do you restore AD? 75. How do you change the DS Restore admin password? 76. Why can't you restore a DC that was backed up 4 months ago? 77. What are GPOs? 78. What is the order in which GPOs are applied? 79. Name a few benefits of using GPMC. 80. What are the GPC and the GPT? Where can I find them? 81. What are GPO links? What special things can I do to them? 82. What can I do to prevent inheritance from above? 83. How can I override blocking of inheritance? 84. How can you determine what GPO was and was not applied for a user? Name a few ways to do that. 85. A user claims he did not receive a GPO, yet his user and computer accounts are in the right OU, and everyone else there gets the GPO. What will you look for? 86. Name a few differences in Vista GPOs 87. Name some GPO settings in the computer and user parts. 88. What are administrative templates? 89. What's the difference between software publishing and assigning? 90. Can I deploy non-MSI software with GPO? 91. You want to standardize the desktop environments (wallpaper, My Documents, Start menu, printers etc.) on the computers in one department. How would you do that? 92. What is an IP address? 93. What is a subnet mask? 94. What is ARP? 95. What is ARP Cache Poisoning? 96. What is the ANDing process? 97. What is a default gateway? What happens if I don't have one? 98. Can a workstation computer be configured to browse the Internet and yet NOT have a default gateway? 99. What is a subnet? 100. What is APIPA? 101. What is an RFC? Name a few if possible (not necessarily the numbers, just the ideas behind them) 102. What is RFC 1918? 103. What is CIDR? 104. You have the following Network ID: 192.115.103.64/27. What is the IP range for your network? 105. You have the following Network ID: 131.112.0.0. You need at least 500 hosts per network. How many networks can you create? What subnet mask will you use? 106. You need to view at network traffic. What will you use? Name a few tools 107. How do I know the path that a packet takes to the destination? 108. What does the ping 192.168.0.1 -l 1000 -n 100 command do? 109. What is DHCP? What are the benefits and drawbacks of using it? 110. Describe the steps taken by the client and DHCP server in order to obtain an IP address. 111. What is the DHCPNACK and when do I get one? Name 2 scenarios. 112. What ports are used by DHCP and the DHCP clients? 113. Describe the process of installing a DHCP server in an AD infrastructure. 114. What is DHCPINFORM? 115. Describe the integration between DHCP and DNS. 116. What options in DHCP do you regularly use for an MS network? 117. What are User Classes and Vendor Classes in DHCP? 118. How do I configure a client machine to use a specific User Class? 119. What is the BOOTP protocol used for, where might you find it in Windows network infrastructure? 120. DNS zones – describe the differences between the 4 types. 121. DNS record types – describe the most important ones. 122. Describe the process of working with an external domain name 123. Describe the importance of DNS to AD. 124. Describe a few methods of finding an MX record for a remote domain on the Internet. 125. What does "Disable Recursion" in DNS mean? 126. What could cause the Forwarders and Root Hints to be grayed out? 127. What is a "Single Label domain name" and what sort of issues can it cause? 128. What is the "in-addr.arpa" zone used for? 129. What are the requirements from DNS to support AD? 130. How do you manually create SRV records in DNS? 131. Name 3 benefits of using AD-integrated zones. 132. What are the benefits of using Windows 2003 DNS when using AD-integrated zones? 133. You installed a new AD domain and the new (and first) DC has not registered its SRV records in DNS. Name a few possible causes. 134. What are the benefits and scenarios of using Stub zones? 135. What are the benefits and scenarios of using Conditional Forwarding? 136. What are the differences between Windows Clustering, Network Load Balancing and Round Robin, and scenarios for each use? 137. How do I work with the Host name cache on a client computer? 138. How do I clear the DNS cache on the DNS server? 139. What is the 224.0.1.24 address used for? 140. What is WINS and when do we use it? 141. Can you have a Microsoft-based network without any WINS server on it? What are the "considerations" regarding not using WINS? 142. Describe the differences between WINS push and pull replications. 143. What is the difference between tombstoning a WINS record and simply deleting it? 144. Name the NetBIOS names you might expect from a Windows 2003 DC that is registered in WINS. 145. Describe the role of the routing table on a host and on a router. 146. What are routing protocols? Why do we need them? Name a few. 147. What are router interfaces? What types can they be? 148. In Windows 2003 routing, what are the interface filters? 149. What is NAT? 150. What is the real difference between NAT and PAT? 151. How do you configure NAT on Windows 2003? 152. How do you allow inbound traffic for specific hosts on Windows 2003 NAT? 153. What is VPN? What types of VPN does Windows 2000 and beyond work with natively? 154. What is IAS? In what scenarios do we use it? 155. What's the difference between Mixed mode and Native mode in AD when dealing with RRAS? 156. What is the "RAS and IAS" group in AD? 157. What are Conditions and Profile in RRAS Policies? 158. What types or authentication can a Windows 2003 based RRAS work with? 159. How does SSL work? 160. How does IPSec work? 161. How do I deploy IPSec for a large number of computers? 162. What types of authentication can IPSec use? 163. What is PFS (Perfect Forward Secrecy) in IPSec? 164. How do I monitor IPSec? 165. Looking at IPSec-encrypted traffic with a sniffer. What packet types do I see? 166. What can you do with NETSH? We can copy network setting and configure complex option of network parameters 167. How do I look at the open ports on my machine? A. Netsh -aon How is virtualization like a dual-boot system? A: It is nothing like a dual-boot system. A dual-boot system still runs only one OS at a time, has no idealized hardware environment, and provides no encapsulation or portability. Q: What do you mean virtual machines are portable? A: Because virtual machines are encapsulated in their .vmdk files and VMware provides an idealized hardware environment, virtual machines can be moved from one ESX Server to the next either using Vmotion or importing the .vmdks. Q: How is VMware more stable than, say, a new physical server? A: The idealized hardware provided by VMware provides a consistent virtual hardware environment that increases that stability of your virtual machines independent of the underlying physical hardware. Q: Is any installation method better than any other? A: No. Whichever installation method you're comfortable with and that produces a good build is the one for you. Q: I'm having problems with my installation. What should I do? A: Ensure that the hardware you're loading ESX Server on is supported. The same goes for the configuration. If you are certain the hardware and configuration are supported, then run the vm-support script mentioned previously. Q: Why does this chapter include only the graphical installer method? A: It's the recommended installation method from VMware and one that many in the x86-world are the most comfortable with. If you wish to try it another way, VMware offers a very complete installation document covering the various installation methodologies. Q: When I copy my virtual machine and try to run it on my network, I get hostname already exists and IP address already exists errors. I thought I could simply copy my virtual machine. What is the problem? A: You can copy your virtual machine, which is why you're running into this problem. The copy is an exact copy. Thus, you need to change the hostname, IP address, and even the computer's SID (if it has one). Q: Can I move my Gold Master to my other ESX Servers? A: Yes, it's a recommended time-saver. If your ESX Servers share a LUN, that too is a way to access your Gold Master or your VMlibrary for that matter. Q: Are there any limitations to the number of virtual machines I can run on my ESX Server? A: Yes. Each ESX Server allows for only 80 virtual CPUs and 200 registered virtual machines. Q: Can I take a virtual machine running on VMware Workstation or GSX and run it in ESX? A: It depends. The process is not as simple as cutting and pasting. There is a specific import process required for migrating virtual machines from either Workstation or GSX into ESX. Access the following link for the exact instructions: http://www.vmware.com/pdf/mobility_guide.pdf. Q: Do you need to tweak the settings of your virtual machines after you've built them? A: No. VMware has configured the defaults of your build to suit most server loads. However, depending on the profile of your server and the resource intensiveness of the service it's providing, you may want to consider tweaking some of the default settings to better ensure service stability and reliability. Q: Are there more advanced features than the ones detailed in this chapter? A: Yes… a lot more. Q: Is clustering more stable in VMware? A: We find that the idealized hardware, in combination with VMware's improvements in clustering support, has made virtual clustering very stable. Q: Can you Vmotion a cluster? A: That depends on the cluster type and how it is configured. Clusters using Raw Device Mapping in virtual mode can be moved with Vmotion according to VMware documentation. Q: Does VMware support NIC teaming? A: Yes, and it's a very good idea to configure your ESX Server, especially if it's for production, with teamed NICs. This will provide hardware fault tolerance in case one NIC fails. Q: How many physical NICs do I need on my ESX Server? A: That depends on the number of virtual machines and the network traffic they produce. You should have a minimum of two: one for your Service Console and one dedicated to your virtual machines. Q: If I'm building a cluster using Microsoft Clustering Service, what's the best configuration for my heartbeat NIC? A:For a Cluster in a Box, create a VMnet that your nodes of your cluster can attach their heartbeat NICs. Q: Can you attach virtual machines on any ESX Server to a VMnet? A: No. Only virtual machines on the ESX Server that the VMnet resides can attach to it. Q: Why should you pay for a p-to-v toll when there are a number of ways to do it for free? A: If you don't have the time or inclination to learn the manual process or need the assurance of a vendor for your physical-to-virtual migrations, then a tool that comes with support is a very reasonable option. Q: What takes the longest in the p-to-v process? A: Transferring the data of the physical server into either an image file or the virtual server itself. That's why tweaking your network settings for optimal throughput is essential when p-to-v'ing a server. Q: Can you create complete backups of your physical servers and then recover them into virtuals? A: I've used NTBackup to back up Windows 2000 Professional and Windows XP, and created virtuals out of .bkf files. It works but there's a bit of futzing around with the virtual once it is running. Try it. Q: What's the most essential part of creating a smooth migration plan? A: Practice. No matter what the tool or process, practice it and learn its gotchas and the workarounds. No matter what method you use, there will be times when it won't go as planned. Practicing your p-to-v process on a number of physical platforms and disk configurations allows you to become more adept once you're doing it for real. Q: Will my software vendor support my application in a VMware environment? A: You'll need to contact your specific software or applications vendor to find out; however, an increasing number of software vendors support virtualized environments. Once you've migrated your application from a physical to virtual environment it's very easy to migrate back to a physical environment for vendor support. An excellent document provided by VMware can be found at the following link: www.vmware.com/pdf/ms_support_statement.pdf. Q: What are the best enablers to help ensure our server consolidation is a success? A: Engaging with the lines of business and application owners not only assists in attaining an actionable schedule, but also develops a highly collaborative environment that facilitates buy-in and support for your project. In addition it will be difficult to incorporate rationalization into your project unless you are working directly with the business or application owners. Q: What tools do you recommend for a server consolidation or virtualization project? A: It's imperative to have a robust and comprehensive tool for capacity planning, including historical data. This tool can be utilized in every phase of your project. Other tools to support the project include modeling tools used in test consolidation scenarios. Finally, you'll need to evaluate and document tools and processes for each technology you wish to consolidate. The migration tools will need to support all the platforms you wish to use in your migration scenarios. Q: What is the VMlibrary? A: The VMlibrary (/vmlib) is simply a directory on your ESX Server that lets you organize the tools and files you need to manage and maintain your virtual infrastructure, Q: Can ISOs be shared between ESX Servers? A: If you place your VMlibrary on a LUN that's shared amongst your ESX Servers, you can share your ISO images or anything else you place in your VMlibrary. Q: Why is Vmotion so cool? A: Try it…and then imagine the possibilities and applications. You'll be a convert soon enough. Q: You mentioned that additional ISVs were creating management capabilities for virtual infrastructures in their products. Which ones? A: Look at HP Insight Manager, Dell OpenManage, IBM Director, BMC's Patrol product line, Computer Associates' Unicenter, and many others. Q: I can't add a new virtual hard drive to my virtual machine. What should I do? A: You may not have the appropriate permissions to add virtual hardware to the VM, or the VM may be powered on and won't allow the addition of virtual hardware while powered on. Q: I just created a new virtual machine and attached to an existing disk. Every time I power on the VM, I get a blue screen. What could the problem be? A: Make sure the OS type that you selected when you created the VM matches the OS type installed on the virtual disk. For example, if you selected Windows 2003 Standard for the VM when you created it, but the existing virtual disk has Windows 2000 Standard installed, you'll probably encounter issues. Q: I followed the directions for Active Directory authentication, and I still can't log in using an account and password in AD. What should I do? A: Check the time on your ESX Server and Active Directory and make sure they're synced up. Kerberos is very sensitive to being out of sync and could reject credentials if the time is not within specific limits. You can also review the System event logs for clues. Q: What is the most important aspect of deploying ESX Server and virtual machines? A: The ability to provide service at least as good as that which you had with physical servers. With adherence to best practices, you should easily be able to provide this and exceed it by a phenomenal degree. Q: ISOs have been mentioned in several of the chapters. Why are they so important? A: Good administrators strive to never leave their chairs, cubes, or offices. If they do, they may just run into a user (we're kidding, of course). Having a library of ISOs can help you in this endeavor. In addition, they run a lot faster than regular CDs. Q: What will happen if I deploy systems management software on the ESX Server itself? A: If you're going to do this, make sure you allocate enough memory so that the application doesn't impact the performance of your ESX Server and thus your virtual machines. Also, use a system management package that is supported and test your installation on your ESX Server thoroughly. If you notice a degradation of performance, contact the systems management software vendor. The major vendors have instructions and best practices for deploying their products onto ESX Server. Q: What is the most important best practice to follow? A: The one that ensures your smooth evolution into a virtual infrastructureeducation. Learn every aspect of a virtual environment to the best of your ability. Be passionate about it and you'll reap the rewards. See the recommended reading list, troll the VMware Web site regularly, as well as other Web sites dedicated to virtualization such as p2v.net, vmguru.com, and virtual-strategy.com. Q: Which version of VMware ESX Server supports Boot from SAN? A: ESX Server 2.5 supports Boot from SAN but has the following limitations: ESX server had to be installed in boot from SAN mode, the HBA can only be used by the Service Console, LUN masking should be used to restrict other ESX servers from the boot LUN, the HBA of the boot LUN must be a QLogic HBA, and the boot LUN must be the lowest numbered LUN controlled by the storage processor. Q: Where are log files for VMware ESX Server written to? A: /var/logs/vmware Q: What do you do if you forget the root password of the Service Console? A: You will need to boot into single-user mode from the Service Console by selecting linux from the LILO boot menu and appending -s to your boot choice. This will boot the console into single-user mode and will allow you to use the passwd command to change the root user password. Q: Why do I still see processes for my virtual machine when running the ps command on the Service Console even though my virtual machine is powered down? A: If there is still a virtual console session running for your VM, you will still see processes associated with it for mouse, keyboard, and screen (MKS) even though it is powered off. Q: I accidently unmounted the VMFS volume on my ESX Server. How can I re-mount the volume without re-booting A: You can type mount t vmfs vmfs /vmfs Q: What software is qualified for use with VMware 2.5.1? A: Please see http://vmware.com/pdf/esx_backup_guide.pdf for an up-to-date list of software that's compatible with ESX. Q: What SANs are compatible with ESX Server? A: Please see http://vmware.com/pdf/esx_SAN_guide.pdf for details on ESX-to-SAN server compatibility. Q: What are the certified backup tools for ESX? A: Please see http://vmware.com/support/esx25/doc/backup_tools_links.html. Q: Can I back up my entire virtual machine from the Service Console? A: Yes, but it is not advised. The console services should be left alone to manage the entire virtual machine infrastructure. It's best that backups be performed by separating the applications and data from the operating systems because backups can become quite large very quickly. You should consider a backup of the environments that change frequently (data and applications) with an agent specifically designed to perform this function. A backup of those virtual disks that change infrequently and need VMFS formats should be backed up from the Service Console. These console-based backups should be performed in a powered-down or suspended approach (preferred), or a suspended environment using redo logs as an alternative. All backups performed from a systems console mode must be restored in an all-or-nothing approach. Recovery for a single file or directory can only be accomplished via a backup agent or from a backup to a SAN environment using a variety of different recovery/restoral techniques. Q: I'm not able to connect to the Service Console over the network. What could the issue be? A: You may have allocated the Service Console NIC to the VMkernel. Use vmkpcidivyi to reassign the NIC to the Service Console. Q: I have a virtual machine that did not start up correctly, but now I can't power it down from the MUI or Virtual Center. How can I get this VM to shut down? A: You can use the vmware-cmd utility to force a hard power down. The following syntax should work: vmware-cmd /path-to-vm/vm-directory/vm.vmx stop hard Q: I find using commands to be very difficult. Why can't I use X Windows on the Service Console? A: You actually could run the X Windows system on the Service Console, but it will eat up valuable resources that are needed by the system to manage all the processes related to Virtualization. VMware specifically says not to run X Windows on the Service Console. So, it's best to just buck up and deal with it. Q: Is there a way to mount the vmfs volumes if they accidentally get unmounted without having to reboot? A: Yes. You can run mountt vmfs vmfs /vmfs. Q: How do I check the speed and duplex setting of the Service Console NIC? Also, how do I change it if needed? A: You'll need to cat out the eth0.info file for your type of adapter. This file can be found at /proc/net/type-of-nic/eth0.info. To give you an example, our server has an Intel Pro 100 Nic for the Service Console, so for us to find the speed and duplex information we would type: cat /proc/net/PRO_LAN_Adapters/eth0.info. Q: How long has Xen been around? A: Since 2004, and they're located in Palo Alto, California. Hmm…what other virtualization company is in Palo Alto? Q: What is a hypervisor? A: In VMware parlance, it's the virtualization layer. Q: If I can't get a SAN, will local storage with a RAID device be sufficient? A: Absolutely. You won't get some of the cooler tools like VMotion, but being virtual on local storage is better than remaining physical. 1) What is virtual SMP? The VMware Virtual Symmetric Multi-Processing (SMP) product allows virtual infrastructure administrators to construct virtual machines with multiple virtual processors 2 ) define virtualization ? Virtualization is the process of implementing multiple operating systems on the same set of physical hardware to better utilize the hardware. The process of virtualization involves a virtualization layer called a hypervisor that separates the physical hardware from the virtual machines. This hypervisor manages the virtual machines’ access to the underlying hardware components. 3 ) H/ W initiator and s/W initiator ? H/ W initiator will initiate the authentication mechanism to the storage processor without the intervention of OS. S/W inititator will initiate the connectivity with the help of OS. Its also the software which does this. Where as in H/W initiator there should be a physical card to initiate the process. 4 ) Main difference between ESX 2.X & 3.X? 5) what are VLANS? Virtual LAN (vLAN) A logical LAN configured on a virtual or physical switch that provides efficient traffic segmentation, security, and efficient bandwidth utilization by providing traffic only to the ports configured for a respective vLAN. Trunk port (trunking) A trunk port on a switch is a port that listens for and knows how to pass traffic for all vLANs configured on the switch. NIC team The aggregation of physical ports to form a single logical communication channel. vmxnet adapter A virtualized network adapter operating inside a guest operating system. The vmxnet adapter is a high-performance virtual network adapter that operates only if VMware Tools have been installed. The vmxnet adapter is identified as ‘‘flexible’’ in the virtual machine properties. vlance adapter A virtualized network adapter operating inside a guest operating system. The vlance adapter is the default adapter used until the VMware Tools installation has been completed. e1000 adapter A virtualized network adapter that emulates the Intel e1000 network adapter. The e1000 network adapter is most common in 64-bit virtual machines. 6) what is TOE ? An ESX Server host can initiate communication with an iSCSI storage device by using a hardware device with dedicated iSCSI technology built into the device, or by using a software-based initiator that utilizes standard Ethernet hardware and is managed like normal network communication. Using a dedicated iSCSI HBA that understands the TCP/IP stack and the iSCSI communication protocol provides an advantage over software initiation. Hardware initiation eliminates some processing overhead in the Service Console and VMkernel by offloading the TCP/IP stack to the hardware device. This technology is often referred to as the TCP/IP Offload Engine (TOE). When you use an iSCSI HBA for hardware initiation, the VMkernel needs only the drivers for the HBA and the rest is handled by the device. 7 ) 802.3 tagged and untagged? 8) What is teaming ? Explain the types ? NIC teaming requires that all uplinks be connected to physical switches that belong to the same broadcast domain. Virtual Switch to Physical Switch To eliminate a single point of failure, the physical network adapters in NIC teams set to use the vSwitch port-based or source MAC-based load-balancing policies can be connected to different physical switches; however, the physical switches must belong to the same Layer 2 broadcast domain. Link aggregation using 802.3ad teaming is not supported with either of these load-balancing policies. 9 ) LUN Masking ? In addition to configuring zoning at the fibre channel switches, LUNs must be presented, or not presented, to an ESX Server. This process of LUN masking, or hiding LUNs from a fibre channel node, is another means of ensuring that a server does not have access to a LUN. As the name implies, this is done at the LUN level inside the storage device and not on the fibre channel switch. More specifically, the storage processor (SP) on the storage device allows for LUNs to be made visible or invisible to the fibre channel nodes that are available based on the zoning configuration. The hosts with LUNs that have been masked are not allowed to store or retrieve data from those LUNs. Zoning provides security at a higher, more global level, whereas LUN masking is a more granular approach to LUN security and access control. The zoning and LUNmasking strategies of your fibre channel network will have a significant impact on the functionality of your virtual infrastructure. What is iSCSI? iSCSI Network Storage As a response to the needs of not-so-deep-pocketed network administrators, Internet Small Computer Systems Interface (iSCSI) has become a strong alternative to fibre channel. The popularity of iSCSI storage, which offers both lower cost and increasing speeds, will continue to grow as it finds its place in virtualized networks. Understanding iSCSI Storage Networks iSCSI storage provides a block-level transfer of data using the SCSI communication protocol over a standard TCP/IP network. By using block-level transfer, as in a fibre channel solution, the storage device looks like a local device to the requesting host. With proper planning, an iSCSI SAN can perform nearly as well as a fibre channel SAN — or better. This depends on other factors, but we can dive into those in a moment. And before we make that dive into the configuration of iSCSI with ESX, let’s first take a look at the components involved in an iSCSI SAN. Despite the fact that the goals and overall architecture of iSCSI are similar to fibre channel, when you dig into the configuration details, the communication architecture, and individual components of iSCSI, the differences are profound. The components that make up an iSCSI SAN architecture, shown in Figure 4.19, include: Hardware initiator A hardware device referred to as an iSCSI host bus adapter (HBA) that resides in an ESX Server host and initiates storage communication to the storage processor (SP) of the iSCSI storage device. Software initiator A software-based storage driver initiator that does not require specific hardware and transmits over standard, supported Ethernet adapters. Storage device The physical device that houses the disk subsystem upon which LUNs are built. Logical unit number (LUN) A logical configuration of disk space created from one or more underlying physical disks. LUNs are most commonly created on multiple disks in a RAID configuration appropriate for the disk usage. LUN design considerations and methodologies will be covered later in this chapter. Storage processor (SP) A communication device in the storage device that receives storage requests from storage area network nodes. Challenge Handshake Authentication Protocol (CHAP) An authentication protocol used by the iSCSI initiator and target that involves validating a single set of credentials provided by any of the connecting ESX Server hosts. Ethernet switches Standard hardware devices used for managing the flow of traffic between ESX Server nodes and the storage device. iSCSI qualified name (IQN) The full name of an iSCSI node in the format of iqn.- .com.domain:alias. For example, iqn.1998-08.com.vmware:silo1-1 represents the registration of vmware.com on the Internet in August (08) of 1998. Nodes on an iSCSI deployment will have default IQNs that can be changed. However, changing an IQN requires a reboot of the ESX Server host. 12 ) SAN vs NAS? 14) Explain the features of ESX 3.5 ? 15) ballooning? 16) What is NUMA? 17) Explain resource pools? 18) CPU Affinity advantages and disadvantages? 19 ) Limitations of Virtualization? 20 ) what are the advantages of VMfs-3? 21) why is a LUN locked? 22) what is metadata? 23) what is metadata update? 24 ) what are the file extensions of VMs? 25) command used to mount vmfs volumes? 26) what is a sparse disk? 27) Default Ethernet device on ESX 2.5.x? 28) why do VMs run ; even if the service console is crash on ESX 3.5? 29 ) what is NMI ? 30 ) What is the use of RDM?\ Raw Device Mappings (RDMs) A raw device mapping (RDM) is not direct access to a LUN, nor is it a normal virtual hard disk file. An RDM is a blend between the two. When adding a new disk to a virtual machine, as you will soon see, the Add Hardware Wizard presents the Raw Device Mappings as an option on the Select a Disk page. This page defines the RDM as having the ability to give a virtual machine direct access to the SAN, thereby allowing SAN management. I know this seems like a contradiction to the opening statement of this sidebar; however, we’re getting to the part that oddly enough makes both statements true. By selecting an RDM for a new disk, you’re forced to select a compatibility mode for the RDM. An RDM can be configured in either Physical Compatibilitymode or Virtual Compatibilitymode. The Physical Compatibility mode option allows the virtual machine to have direct raw LUN access. The Virtual Compatibility mode, however, is the hybrid configuration that allows raw LUN access but only through a VMDKfile acting as a proxy. The image shown here details the architecture of using an RDM in Virtual Compatibility mode: So why choose one over the other if both are ultimately providing raw LUN access? Since the RDM in Virtual Compatibility mode uses a VMDK proxy file, it offers the advantage of allowing snapshots to be taken. By using the Virtual Compatibility mode, you will gain the ability to use snapshots on top of the raw LUN access in addition to any SAN-level snapshot or mirroring software. Or, of course, in the absence of SAN-level software, the VMware snapshot feature can certainly be a valuable tool. The decision to use Physical Compatibility or Virtual Compatibility is predicated solely on the opportunity and/or need to use VMware snapshot technology. 31 ) what is SCSI paas thru? 32 ) what is SCSI-2 reservation ? 33 ) why do you check SCSI-queue length? 34) How will you check the performance of the ESX ? 35 ) what information is saved in redo log? 36 ) what log is generated when vm-support command is run? 37 ) After installation of ESX server , root is not able to login ? why ? 38 ) what is ps –auwwwx? 39 ) What is MAX Lun Count? 40 ) TCP / IP Ports 902 & 903? 41 ) what is VMKernel & Service Console? 42 ) Why should I put similar type of OS in same ESX? 43 ) difference between HBA and NIC? 44 ) What type of NIC cards are supported on ESX 3.X? 45 ) How will you check the storage paths? 46 ) What is the use of HA? 47 ) where are the configuration files stored ? what are they? 48 ) where are network setting stored ? 49 ) Is ESX a linux OS? 51 ) Explain VMFS and why it differs from other filesystems? 52) vmware heartbeat port number ? 53) High Availability design & implementation experience Virtualization Technologies (Microsoft, VMWare, Citrix) Workstation technologies Clustered server environments Active Directory & LDAP, XML services Authentications Services (Radius, TACACS) Server/Client DB applications (SAP, Oracle, SQL) Antivirus, ISS, Microsoft Updates DNS/DHCP design (incl MetaInfo software) Content Filtering (ISA Proxy, Websense) Backup Technologies SCOM & SCCM Services 1. Installation and administration of Windows 2000, 2003, and 2008 Servers, SQL clustering using industry tools and best practices. Diagnose and repair hardware and software related issues. 2. System upgrades such as firmware, OS, application, and security patch evaluation and deployment using SMS, patchlink, WSUS, IBM Director, Trend AV, and manual processes. 3. Ability to manage various vendor and homegrown applications as required. 4. Administer and/or troubleshoot Active Directory and related environments such as WINS, DNS, file shares and folder permissioning, user account maintenance, and group policy, as well as server performance tuning. 5. Solid understanding of SAN components using Cisco MDS, McData, EMC ECC, EMC Clariion using Mirrorview and DMX using SRDF 6. Maintain ISO, SOX, and SAS70 awareness and work to increase compliancy when needed. 7. Solid understanding of virtualization technologies, such as VMware ESX. Job Description: 1. Good experience with Microsoft operating systems. 2. Hands on experience with various software applications. 3. Good amount of experience with multiple vendor server hardware, including IBM, Dell, and EMC, HP Blades a STRONG + 4. Intermediate understanding of networking principles, including DHCP, DNS, and TCP/IP. 5. Ability to effectively communicate with all levels of management and team peers. Drawing upon concepts of tools, technologies and methodologies to collaborate with other technical specialists when carrying out assigned duties. Effectively negotiating with technical peers and customers to implement technical solutions. Maintaining skills to the current industry level of certification. Recognizing and articulating job related problems to management. Analyzing technical problems and creating solutions involving the use of existing techniques and/or tools. Performing assigned tasks in accordance with established standards and guidelines. Preparing and recommending technical alternatives involving technology, methodology, tools, processes and solution components. Challenging the validity of given procedures and processes with the intent to enhance and improve a customer solution. Assisting in the identification of new service opportunities. Assisting the Project Manager by providing a technical project coordination role. Liaising with relevant support teams for all clients to ensure they are informed about relevant progress and issues relating to Intel server to be handed over for server management to ensure a smooth transition. Providing coverage for VMWare Server Management teams when no billable project work is available. Abiding by Change Management and Problem Management procedures, including complying with the Service Level Agreements as documented in the Problem Severity matrix. Act on Day to Day House Keeping tasks by using tools & scripts To able to perform in 24 x 7 Environment in shift roaster To able to attend calls on calls basis whenever assigned Work with Change & Problem Management Tools Create regular reports for Management requirements. Desired Experience: VMware ESX and GSX Server support Experience. Strong Knowledge & Experience in Red Hat Enterprise Linux support experience. Good Understanding of trouble shooting & Microsoft Windows Server concepts. Experience in high level diagnostics & troubleshooting of VMWare ESX and GSX server environment. Project experience of design and delivery of server virtualization in an Enterprise environment. Experience in performance tuning of VMWare servers and Virtual sessions and management of servers resources between virtual machines. Experience in backup and recovery of Virtual machines and virtual servers. Experience in P2V, VMotion and VMware virtual center. Good Understanding of virtualization technology. Knowledge and Experience implementing Security hardening measures to the OS on servers IBM,HP and Dell hardware and troubleshooting. Strong storage, hardware and networking experience SKILLS REQUIRED: Extensive knowledge of Windows NT/2000/2003 Servers, Active Directory Strong Knowledge in Active Directory concepts like OU, Sites, GPO, FSMO etc. Create and configure Virtual Machines,, templates, Switches, VM clusters Perform VMware migration activities Troubleshooting for ESX/ESXi hosts and Virtual machines Perform Troubleshooting for VMware HA/DRS, VMotion, Storage, Networking Managing and Troubleshooting Site Topology and replication failures Troubleshooting Windows AD using Resource kit/Support tools Advanced troubleshooting skills in OS related issues Strong knowledge of Windows clustering Strong knowledge on IIS server Server Performance analysis and tuning. Capacity planning / Forecasting Exposure to server hardening Configuration and troubleshooting skills on various RAID technologies (RAID 0+1, RAID 1, RAID 5 etc.) Windows Resource Kit tools like ADmodify.net, ADSI Edit, csvde.exe, ADSI viewer. Exposure to disaster recovery of server OS and Active Directory Excellent communication and documentation skills Responsibilities : System Administration of Windows 2000/2003/2008 System Administration of ESX 3.0/3.5/ESXi Performance Tuning, Active Directory, Security, DNS, Mail Monitor and performance tuning of vSphere ESX/ESXi and Virtual Machine Performance Trouble shooting on x86 H/W platforms Capacity Management and Server consolidation The candidate should have worked in a SLA driven environment. Ability to work in a flexible, team-oriented and constantly changing environment VMWare Interview Questions & Tips 1. VMWare Kernel is a Proprietary Kenral and is not based on any of the UNIX operating systems, it's a kernel developed by VMWare Company. 2. The VMKernel can't boot it by itself, so that it takes the help of the 3rd party operating system. In VMWare case the kernel is booted by RedHat Linux operating system which is known as service console. 3. The service console is developed based up on Redhat Linux Operating system, it is used to manage the VMKernel 4. To restart webaccess service on vmware service vmware-webaccess restart – this will restart apache tomcat app 5. To restart ssh service on vmware service sshd restart 6. To restart host agent(vmware-hostd) on vmware esx server service mgmt-vmware restart 7. Path for the struts-config.xml /usr/lib/vmware/webAccess/tomcat/apache-tomcat-5.5.17/webapps/ui/WEB-INF/ 8. To start the scripted install the command is esx ks=nfs:111.222.333.444:/data/KS.config ksdevice=eth0 location device name 9. Virtual Network in Simple………………. Virtual Nic(s) on Virtual Machine(s) -----> Physical Nic on the ESX Server (Virtual Switch - 56 Ports) -----> Physical Switch Port Should be trunked with all the VLANS to which the VM's need access All the ESX servers should be configured with Same number of Physical Nics (vSwitches) and Connectivity also should be same, So that vMotion succeeds All the Virtual Machines are connected to one vSwitch with Different VLANS, this means the Physical Nic(vSwitch) needs to be trunked with the same VLANS on the Physical Switch Port 10 What are the three port groups present in ESX server networking 1. Virtual Machine Port Group - Used for Virtual Machine Network 2. Service Console Port Group - Used for Service Console Communications 3. VMKernel Port Group - Used for VMotion, iSCSI, NFS Communications 11. What is the use of a Port Group? The port group segregates the type of communication. 12. What are the type of communications which requires an IP address for sure ? Service Console and VMKernel (VMotion and iSCSI), these communications does not happen without an ip address (Whether it is a single or dedicated) 13. In the ESX Server licensing features VMotion License is showing as Not used, why? Even though the license box is selected, it shows as "License Not Used" until, you enable the VMotion option for specific vSwitch 14. How the Virtual Machine Port group communication works ? All the vm's which are configured in VM Port Group are able to connect to the physical machines on the network. So this port group enables communication between vSwitch and Physical Switch to connect vm's to Physical Machine's 15. What is a VLAN ? A VLAN is a logical configuration on the switch port to segment the IP Traffic. For this to happen, the port must be trunked with the correct VLAN ID. 16. Does the vSwitches support VLAN Tagging? Why? Yes, The vSwitches support VLAN Tagging, otherwise if the virtual machines in an esx host are connected to different VLANS, we need to install a separate physical nic (vSwitch) for every VLAN. That is the reason vmware included the VLAN tagging for vSwitches. So every vSwitch supports upto 1016 ports, and BTW they can support 1016 VLANS if needed, but an ESX server doesn’t support that many VM’s. :) 17. What is Promiscuous Mode on vSwitch ? What happens if it sets to Accept? If the promiscuous mode set to Accept, all the communication is visible to all the virtual machines, in other words all the packets are sent to all the ports on vSwitch If the promiscuous mode set to Reject, the packets are sent to inteded port, so that the intended virtual machine was able to see the communication. 18. What is MAC address Changes ? What happens if it is set to Accept ? When we create a virtual machine the configuration wizard generates a MAC address for that machine, you can see it in the .vmx (VM Config) file. If it doesn't matches with the MAC address in the OS this setting does not allow incoming traffic to the VM. So by setting Reject Option both MAC addresses will be remains same, and the incoming traffic will be allowed to the VM. 19. What is Forged Transmits ? What happens if it is set to Accept ? When we create a virtual machine the configuration wizard generates a MAC address for that machine, you can see it in the .vmx (VM Config) file. If it doesn't matches with the MAC address in the OS this setting does not allow outgoing traffic from the VM. So by setting Reject Option both MAC addresses will be remains same, and the outgoing traffic will be allowed from the VM. 20. What are the core services of VC ? VM provisioning , Task Scheduling and Event Logging 21. Can we do vMotion between two datacenters ? If possible how it will be? Yes we can do vMotion between two datacenters, but the mandatory requirement is the VM should be powered off. 22. What is VC agent? and what service it is corresponded to? What are the minimum req's for VC agent installation ? VC agent is an agent installed on ESX server which enables communication between VC and ESX server. The daemon associated with it is called vmware-hostd , and the service which corresponds to it is called as mgmt-vmware, in the event of VC agent failure just restart the service by typing the following command at the service console " service mgmt-vmware restart " VC agent installed on the ESX server when we add it to the VC, so at the time of installtion if you are getting an error like " VC Agent service failed to install ", check the /Opt size whether it is sufficient or not. 23. How can you edit VI Client Settings and VC Server Settings ? Click Edit Menu on VC and Select Client Settings to change VI settings Click Administration Menu on VC and Select VC Management Server Configuration to Change VC Settings 24. What are the files that make a Virtual Machine ? .vmx - Virtual Machine Configuration File .nvram - Virtual Machine BIOS .vmdk - Virtual Machine Disk file .vswp - Virtual Machine Swap File .vmsd - Virtual MAchine Snapshot Database .vmsn - Virtual Machine Snapshot file .vmss - Virtual Machine Suspended State file .vmware.log - Current Log File .vmware-#.log - Old Log file 25. What are the devices that can be added while the virtual Machine running In VI 3.5 we can add Hard Disk and NIC's while the machine running. In vSphere 4.0 we can add Memory and Processor along with HDD and NIC's while the machine running 26. How to set the time delay for BIOS screen for a Virtual Machine? Right Click on VM, select edit settings, choose options tab and select boot option, set the delay how much you want. 27. What is a template ? We can convert a VM into Template, and it cannot be powered on once its changed to template. This is used to quick provisioning of VM's. 23. What to do to customize the windows virtual machine clone,? copy the sysprep files to Virtual center directory on the server, so that the wizard will take the advantage of it. 24. What to do to customize the linux/unix virtual machine clone,? VC itself includes the customization tools, as these operating systems are available as open source. 25. Does cloning from template happens between two datacenters ? Yes.. it can, if the template in one datacenter, we can deploy the vm from that template in another datacenter without any problem. 26. What are the common issues with snapshots? What stops from taking a snapshot and how to fix it ? If you configure the VM with Mapped LUN's, then the snapshot failed. If it is mapped as virtual then we can take a snapshot of it. If you configure the VM with Mapped LUN's as physical, you need to remove it to take a snapshot. 27. What are the settings that are taken into to consideration when we initiate a snapshot ? Virtual Machine Configuration (What hardware is attached to it) State of the Virtual Machine Hard Disk file ( To revert back if needed) State of the Virtual Machine Memory (if it is powered on) 28. What are the requirements for Converting a Physical machine to VM ? An agent needs to be installed on the Physical machine VI client needs to be installed with Converter Plug-in A server to import/export virtual machines 29. What is VMWare consolidated backup ? It is a backup framework, that supports 3rd party utilities to take backups of ESX servers and Virtual Machines. Its not a backup service. 30. To open the guided consolidation tool, what are the user requirements ? The user must be member of administrator, The user should have "Logon as service" privileges - To give a user these privileges, open local sec policy, select Logon as service policy and add the user the user should have read access to AD to send queries 1. Explain the physical topology of Virtual Infrastructure 3 Data Centre ? 2. How do you configure Clusters,Hosts,Resource Pools in VI3 ? 3. What are resource pools & whats the advantage of implementing them ? 4. Explain why Vmware ESX Server is preferred over Virtual Server or Workstation for enterprise implementation ? 5. In what different scenarios or methods can you manage a VI3 ? 6. Explain the difference between access through Virtual Infrastructure Client (vi client), Web access, Service Console access(ssh) ? 7. Explain advantages or features of Vmware Virtual Machine File System (VMFS) ? 8. What are the types of datastores supported in ESX3.0 ? 9. How can you configure these different types of datastores on ESX2.5 ? 10.What is Vmware Consolidate Backup (VCB) ? Explain your work exposure in this area ? 11.How do you configure Vmware Virtual Centre Management Server for HA & DRS ? What are the conditions to be satisfied for this setup ? 12.Explain your work related to below terms : VM Provisioning: Alarms & Even Management: Task Scheduler: Hardware Compatibility List: 13.What SAN or NAS boxes have you configured VMware with ? How did you do that ? 14.What kind of applications or setups you have on you Virtual Machines ? 15.Have you ever faced ESX server crashing and Virtual Centre Server crash? How do you know the cause of these crashes in these cases ? VMware As you probably already know, VMware ESX is an enterprise grade virtualization product by VMware. Unlike VMware Server, VMware ESX does not require an underlying operating system to be loaded first. What this means is that you get the highest virtualization performance that is possible when using VMware ESX Server. So what is VMware Infrastructure (VI)? VI, is really just a product suite. Keep that in mind. There is really no application called "VMware Infrastructure". VI is a bundle of VMware products... What capabilities or options are available for VMware ESX? When you buy a VMware Infrastructure suite, you are really just buying VMware ESX Server, the VMFS file system, and some number of options. No matter which suite or bundle you buy, you MUST get VMware ESX as that is the core virtualization product you will need. So what options are available for VMware ESX? Virtual Center (VC) - VC provides a centralized management console for all VMware ESX servers. If you plan to grow your virtual data center into the ten’s and hundreds, over time, you should have Virtual Center in your plans. To use VMotion, VM HA, VM DRS, and VM consolidated backup, you must purchase Virtual Center. VMotion - Like magic, VMotion can move a running virtual server to another physical server, without interrupting that server’s requests. This can be done for maintenance of hardware or to better balance workload. VMotion requires a SAN be used to store the virtual machines being moved. Virtual SMP- virtual symmetric multi-processing(SMP) option is what allows virtual machines to act as if they have multiple processors, thus improving performance. VMware HA - the high availability (HA) option for ESX server is what moves virtual guest machines from a failed server to a running server. VM HA uses VMotion to accomplish its task. VMware DRS - dynamic resource scheduling (DRS) is a load balancing system. It can be tuned to move virtual machines, or groups of machines, from one server to another based on the CPU, memory, disk, and network demands being placed on those servers. By using VMotion, DRS can move virtual machines automatically, throughout each day, to best balance the server load, and provide optimum performance to users. VMware Consolidated Backup (VCB) - VCB is an application, running on a separate server, that contacts virtual guests, on a schedule, and provides a pass-through to backup the virtual guest data to your third party backup application. VCB is not a backup application in itself but it has the ability to gain access to the VMFS proprietary file system and allow you to backup or restore individual files, inside the file system. What different VMware Infrastructure Suites are available? There are three VMware Infrastructure Suites available: Starter, Standard, and Enterprise. Here is how they compare: VMware Infrastructure Starter Edition - only ESX Server & VMFS - no SAN storage, up to 4 CPU and 8GB of RAM per server, starting cost about $1000 per server VMware Infrastructure Standard Edition - only ESX Server, VMFS, SAN storage, and Virtual SMP, starting cost about $3750 per server VMware Infrastructure Enterprise Edition - includes ESX Server, VMFS, Virtual SMP, VM HA, VM DRS, and VCB, starting cost about $6000 per server Also, keep in mind that no matter which option you choose if you want to use centralized management and/or you want to use features like VMotion, VM HA, or VM DRS, you must purchase Virtual Center separately, at a cost of approximately $5000. Which VMware ESX Server / Infrastructure Suite is right for me? Now that you know what options are available for ESX Server and can see all the different VMware Infrastructure suites that are available, which do you choose? That question can be answered by finding out which options you require and matching that up with the right suite. The centralized management of Virtual Center is a huge benefit anytime you have more than just a couple of servers. You should know that you can purchase some of the options like VM HA, VM DRS, VCB, and SMP separately, if you just need one or two of these options. In general, I would recommend the starter edition for those who just have a single server to virtualize. Beyond that, I would recommend just jumping to the enterprise edition if your company can justify the costs. VMware Infrastructure can do some truly amazing things when it has all the capabilities that are available. Summary In summary, choosing the right VMware ESX / Virtual Infrastructure suite can be difficult if you don't have all the information you need to make a comparison. In this article, you learned the VMware ESX Server options & capabilities that are available as well as the VMware Virtual Infrastructure Editions that you can choose from. After reading this article, you should be able to quickly tell which VMware Virtual Infrastructure Edition is right for your company. What is Virtualization? Virtualization is a general and ambiguous term that typically means to run multiple instances of something inside something that was intended to only run a single instance. How do we get virtualization? Well there is no. of options available for this, but VMware, Citrix and Microsoft are front runners in domain. Here are the products from above for the same. 1. VMware ESX and VMware server 2. Citrix Xen 3. Microsoft Hyper-V VMware Server: VMware Server is a free virtualization product for Microsoft Windows and Linux servers. It enables you to quickly provision new server capacity or server consolidation by partitioning a Physical server into multiple virtual machines. It is meant for those businesses who want to optimize use of their technology assets using virtualization. Technology behind VMware Server: Hypervisor – 2 (Hosted Architecture) What is Hosted Architecture? Hosted architecture is where your virtualization software is installed as an application onto the pre-existing host operating system. This means that your virtualization layer relies on your host operating system for device support and physical resource management. VMware Server is a good example of a hosted architecture. Hardware and Software support: 1. Any standard x86 compatible or x-86-64compatible personal computer 2. A wide variety of Windows, Linux, Solaris, and other guest operating systems, Including 64-bit operating systems 3. Two-way Virtual SMP 4. Intel Virtualization Technology (Intel VT) 5. AMD-Virtualization (AMT-V) Where VMware Server does fits for your environment? VMware server suits the requirements and demands of small and medium scale business with non-mission critical processes. It can provide following options to the business resources. 1. Virtual Machines for software development: 1. A common environment matching in both configuration and tools for your entire team 2. Quick rollout of new environments and tools 3. Archive of entire development environments for major projects 2. Virtual Machines for software testing: 1. Platform Testing with Snapshots 2. Platform Testing with Persistent and Non-persistent Disks 3. Virtual Machines for Post-release and Application-Maintenance. 1. It can create base image for you development environment 2. Archive of the development team’s virtual machines used during the development phase 3. Rapid platform availability for quick support tasks and bug investigation 4. Run Windows, Linux, and other operating systems and applications without Software conflicts. 5. Move virtual machines from one physical host to another without having to Reconfigure them. Features of VMware Server: 1. Web-Based Interface Use VMware Infrastructure Web Access (VI Web Access) to perform host and virtual machine configuration for VMware Server 2.0. 1. Create, configure, and delete virtual machines 2. Add and remove virtual machines from the inventory 3. Perform power operations (start, stop, reset, suspend, and resume) on virtual Machines 4. Monitor the operation of virtual machines 5. Generate a Web shortcut to customize the VI Web Access user interface for users, with the option to limit their view to the console or a single virtual machine 6. Generate a VMware Remote Console desktop shortcut that allows virtual machine users to interact directly with the guest operating system outside of a Web browser 7. Configure host-wide VMware Server settings 2. VMware Remote Console VMware Remote Console enables you to interact with the guest operating system running in a virtual machine. You can run VMware Remote Console on the host or a remote client system. After you install it as a Web browser add-on from VI Web Access, VMware Remote Console can run independently from VI Web Access. VMware Remote Console also allows you to connect and disconnect client CD/DVD and floppy devices. 3. Memory Support The maximum amount of memory that can be allocated per virtual machine is 8GB. The amount of memory that can be used by all virtual machines combined is limited only by the amount of memory on the host computer. 4. Number of Network Adapters Supported It can support total of 10 network adapters for a virtual machine. 5. Quiesced Backups of Virtual Machines on Windows On Windows hosts, you can enable the VMware VSS Writer, which uses snapshots to maintain the data integrity of applications running inside the virtual machine when you take backups. 6. Support for High-Speed USB 2.0 Devices If the guest operating system has the appropriate USB 2.0 device drivers, you can use peripherals that require high-speed performance, such as speakers, webcams, next-generation printers and scanners, fast storage devices, MP3 players, DVD-RW drives, and high-capacity CD-ROM jukeboxes. Besides above there are few more such as Additional host operating system support Additional guest operating system support improved 64 bit guest support 64 bit sound driver Native 64 bit support on Linux Improved VIX-API VMCI socket interface Bottlenecks: 1. It puts more of your client's eggs in one basket. If the host machine breaks or needs to be taken offline, several virtual servers will go down. 2. Applications like databases that require a lot of disk activity. The prevailing wisdom is that databases should still run on dedicated physical servers. 3. Time-sensitive applications like Voice over IP (VoIP) may also be poor candidates for virtualization. 4. Virtual Machine overload: Application that are low I/O intensive and low utilization are best candidates for virtualization but need to put restriction on no. of virtual machines that can be handled with ease on physical server. VMware Server at a glance: Architecture Hosted OS Requirements Windows or Linux Typical Use Cases Test & Dev, Production Dedicated Server Required No Centralized Management Option No Ease of Use High Performance Good ESX Server ESX Server is VMware’s flagship enterprise server virtualization platform. It comes in two versions – ESX Server and ESXi Server where the latter has no service console and is the thinnest version available. ESX Server has many optional features like VMotion and VMHA and some built-in features like the VMFS file system. Most end users purchase VMware ESX Server with some set of optional features in a package called VMware Infrastructure. ESX Server is managed by the VMware Infrastructure Client. Its centralized management platform is called Virtual Center. Figure 1: ESX server in Enterprise (Virtual infrastructure) What is the need of ESX Server? If you are an idealist then ESX is just for you. It possesses best approaches to adopt the hardware abstraction and most effective usage of your resources through vast available tools and services so that you can maximize your infrastructure efficiency, reducing operational cost by providing cost effective business continuity. Technology behind ESX: Hypervisor – 1 (Bare Metal) Bare Metal means no OS is required because it has its own kernel derived from Linux with it provides greater resources for the virtual machines, decreased cost of licensing and increased utilization of servers. Where ESX server does fit for your environment? As ESX is enterprise wide solution for virtualization to adopt effective hardware abstraction, it best suits for large enterprises with enormous resources. Hardware and Software support with Features for ESX: Architecture: 1. Bare-metal architecture: VMware ESX inserts a robust virtualization layer directly on the server hardware for near-native virtual machine performance, reliability and scalability. Fig: Hypervisor (Bare metal) 2. Small Footprint: VMware ESXi’s 32MB disk footprint is a fraction of the size of a general purpose operating system, reducing complexity and providing unmatched security and reliability. 3. Server Integration: VMware ESXi is available built into server hardware as an embedded component, simplifying and speeding deployment of virtualization. 4. CPU virtualization: Increase server utilization without the risk of critical services being starved for CPU resources. VMware ESX uses intelligent process scheduling and load balancing across available processors to manage the execution of virtual machine processing. 5. Storage in ESX Server: Leverage high performance shared storage to centralize virtual machine file storage for greater manageability, flexibility and availability. Virtual disk files: Add or delete a VMware ESX server from a VMFS volume without pausing or halting the processing of other instances of VMware ESX VMFS cluster file system: Leverage high performance shared storage to centralize virtual machine file storage for greater manageability, flexibility and availability Logical volume manager: Manage the interaction between the physical storage arrays and VMFS with flexibility and reliability Raw device mapping: Optionally, map SAN LUNs directly to a virtual machine in order to enable application clustering and array-based snapshot technology while profiting from the manageability benefits of VMFS Fiber Channel HBA consolidation: Share expensive storage network components across many virtual machines while maintaining hardware fault tolerance Write-through I/O: Ensure precise recovery of virtual machines in the event of server failure. Write-through I/O enables virtual machines to have the same recovery characteristics as a physical system running the same operating system. Boot from SAN: Run VMware ESX installations on diskless configurations of blade and rack mount servers by booting from SAN. Simplify backups and disaster recovery by eliminating the need to separately backup local attached server disks VMFS: (Virtual Machine File System) VMware Virtual Machine File System is a high performance cluster file system which provides storage virtualization that is optimized for virtual machines. Each virtual machine is encapsulated in a small set of files; and VMFS is the default storage management interface for these files on physical SCSI disks and partitions. Fig: VMFS allows sharing of storage for multiple ESX servers Features of VMFS: The technical features of VMFS that make it suitable for use in a virtual environment include: 1. Automated file system with hierarchical directory structure 2. Optimization for virtual machines in a clustered environment 3. Lock management and distributed logical volume management 4. Dynamic data store expansion by spanning multiple storage extents 5. Clustered file system with journal logging for fast recovery 6. Encapsulation of the entire virtual machine state in a single directory Benefits of VMFS: 1. Automated Cluster File System Capability 2. Optimizes VM Access 3. Encapsulates the Entire VM State in a Single Directory 4. Simplifies Provisioning and Administration of VMs 5. Provides Distributed Infrastructure Services for Multi-ESX Servers 6. Facilitates Dynamic Growth 7. Intelligent Cluster Volume Management 8. Enables HA with Lower Management Overhead 9. Simplifies Disaster Recovery VMFS V/S other file systems: Conventional file systems allow only one server to have read-write access to the same file at a given time. In contrast, VMFS is a cluster file system that leverages shared storage to allow multiple instances of ESX Server concurrent read and write access to the same storage resources. VMFS also has distributed journaling to allow fast and resilient recovery across these multi-server resource pools. On-disk locking in VMFS ensures that a virtual machine is not powered on by multiple installations of ESX Server at the same time. With VMware HA enabled, if a server fails the on-disk lock for each virtual machine is released, allowing the virtual machine to be restarted on other physical servers. Moreover, VMFS provides the VM snapshot capabilities so necessary for disaster recovery, and is the interface which VMware Consolidated Backup (VCB) leverages to provide proxy backup of virtual environments. VMFS does not have every feature found today in other CFS and CVM systems. However there is no other CFS/CVM that provides the capabilities of VMFS. Its distributed locking methods forge the link between the VM and the underlying storage resources in a manner that no other CFS or CVM can equal. The unique capabilities of VMFS allow VMs to join a cluster seamlessly, with no management overhead. 6. Networking in ESX Server: Network virtual machines like physical machines. Build complex networks within a single VMware ESX server or across multiple installations of VMware ESX for production deployments or development and testing purposes. Virtual NICs: Configure each virtual machine with one or more virtual NICs. Each of those network interfaces can have its own IP address and even its own MAC address. As a result, virtual machines are indistinguishable from physical machines from a networking standpoint Virtual switches: Create a simulated network within a VMware ESX server with virtual switches that connect virtual machines. Expanded port configuration policies: Simplify port configuration by utilizing a single configuration object across large groups of ports. The configuration object specifies all information needed to enable a port: NIC teaming policy (now per port instead of per virtual switch), VLAN tagging, Layer 2 security, and traffic shaping. VLAN: Overlay a logical LAN on top of physical LANs to isolate network traffic for security and load segregation purposes. VMware ESX VLANs are compatible with standard VLAN implementations from other vendors. Modify network configurations without having to change actual cabling and switch setups. VLANs keep broadcast traffic limited to the VLAN, reducing the network load of broadcast packets on other switches and network segments. Performance and Scalability: VMware ESX delivers unparalleled performance and scalability. With VMware ESX, even the most resource intensive production applications such as databases, ERP and CRM can be virtualized. 1. Enhanced virtual machine performance: Benefit from better virtual machine performance in VMware ESX. Performance improvements have been achieved through: Networking performance optimization: Reduce the CPU overhead associated with processing network i/ Support for hardware nested page tables: Optimize memory translation time between guest operating systems and physical memory Support for large memory pages: Improve memory access efficiency for guest operating systems and the Hypervisor Support for Para virtualized Linux guest operating systems (Linux kernel 2.6.21 onwards). Run higher levels of performance through virtualization-aware operating systems 2. Advanced memory management: RAM over-commitment: Increase memory utilization by configuring virtual machine memory that safely exceeds the physical server memory. For example, the sum of the memory of all virtual machines running on a server with 8GB physical memory can be 16GB Transparent page sharing: Utilize available memory more efficiently by storing memory pages identical across multiple virtual machines only once. For example, if several virtual machines are running Windows Server 2003, they will have many identical memory pages. Transparent page sharing consolidates those identical pages into a single memory location. Memory ballooning: Shift memory dynamically from idle virtual machines to active ones. Memory ballooning artificially induces memory pressure within idle virtual machines, forcing them to use their own paging areas and release memory for active virtual machines. 3. Improved power management: Lower the data center utility bill with improved power management. VMware ESX enters a low power “halt” state when a CPU is not scheduled. 4. 4-Way Virtual SMP(Symmetric multiple processor): Enable a single virtual machine to use up to four physical processors simultaneously. VMware ESX extends this unique feature from two to four processors. With 4-way Virtual SMP even the most processor intensive software applications like databases and messaging servers can be virtualized. 5. 64GB RAM for virtual machines: Run the most memory-intensive workloads in virtual machines with a memory limit extended to 64GB. 6. Support for powerful physical server systems: Take advantage of very large server systems with up to 32 logical CPUs and 256GB RAM for large scale server consolidation and DR projects. 7. Support for up to 128 powered-on virtual machines: Take advantage of very large server systems for enterprise-class server consolidation and containment with support for up to 128 powered on virtual machines on a single server. 8. Flexible virtual switches: Scale up to handle more virtual machines. Virtual switches can be created with any number of ports from 8 to 1016, and up to 248 virtual switches are supported per host. 9. Wake-on LAN: Enable higher consolidation ratios by allowing virtual machines to go on stand-by mode when not used. Interoperability: VMware ESX is the only virtualization platform optimized, rigorously tested and certified across the complete IT stack of servers, storage, operating systems, and software applications allowing for enterprise-wide standardization. 1. Hardware: VMware ESX has been certified with industry-leading rack, tower and blade servers from Dell, Fujitsu Siemens, HP, IBM, NEC, Sun Microsystems and Unisys as well as servers that conform to Intel white-box standard specifications. VMware ESXi is integrated into server hardware guaranteeing that virtualization works out of the box. 2. Storage: VMware ESX is certified with a wide range of storage systems from, Dell, EMC, EqualLogic, Fujitsu, Fujitsu Siemens, HP, Hitachi Data Systems, IBM, NEC, Network Appliance, StorageTek, Sun Microsystems and 3PAR and many other vendors. Heterogeneous storage arrays: Utilize a wide variety of heterogeneous storage devices in the same VMFS volume NAS and iSCSI SAN support: By supporting lower-cost, more easily managed shared storage, VMware ESX further reduces total cost of ownership of IT environments. Advanced VMware Infrastructure features like VMotion and VMware HA are fully supported with NAS and iSCSI environments 4GB Fibre Channel SAN support: Centralize management and configuration of all VMware ESX servers in VirtualCenter. Local SATA storage support: Use select servers with local SATA storage to further lower total cost of ownership while consolidating workloads 3. Networking: Use high performance networking such as 10 Gig E and Infiniband with VMware ESX 3.5 and VMware ESXi 3.5 for the most network intensive workloads 4. Operating systems: Run any software application in VMware virtual machines. 64-bit guest operating system support Solaris 10 operating system support Windows Vista operating system support Ubuntu guest operating system support 5. Software applications with third party systems management products through Web services APIs provided by the VMware Infrastructure SDK. 6. Support for other virtual machine formats: VMware ESX can run virtual machines created in non-VMware formats. Using the free VMware Virtual Machine Importer users can run Microsoft® Virtual Server and Virtual PC, and Symantec® LiveState Recovery virtual machines in VMware ESX. Management: 1. Remote Command Line Interface. Manage VMware ESXi through a remote execution environment that can run VMware ESX command scripts. 2. Advanced manageability and usability features: VMware ESX enables management of entire virtualized IT environment. 3. SMI-S-Compliant Management Interfaces: Monitor virtual storage using any standard SMI-S-aware storage management tool. 4. Virtual Infrastructure Client: Manage VMware ESX, virtual machines, and (optionally) VMware vCenter Server with a common user interface. 5. Virtual Infrastructure Web Access: Manage VMware ESX with simple Web interface (formerly known as the Management User Interface, or MUI). 6. Virtual machine shortcuts: Enable self-help for end users with direct access to virtual machines through a Web browser. 7. Remote devices: Install software in a virtual machine running on a server from the CD-ROM of a desktop without leaving your desk. 8. Agent-less Hardware Management with CIM: The Common Information Model (CIM) provides a protocol for monitoring hardware health and status through Virtual Center or CIM-compatible 3rd party tools. Fig: ESX-Virtual Center Resource Optimization: It defines advanced resource allocation policies for virtual machines to improve service levels to software applications. Establish minimum, maximum, and proportional resource shares for CPU, memory, disk and network bandwidth. Modify allocations while virtual machines are running. Enable applications to dynamically acquire more resources to accommodate peak performance. 1. CPU capacity prioritization: CPU capacity is assigned to virtual machines on a “fair share” basis and CPU resource controls also allow an absolute minimum level of CPU capacity to be provided to critical virtual machines 2. Storage I/O traffic prioritization: Ensure that critical virtual machines receive priority access to storage devices. I/O traffic from virtual machines to disk can be prioritized on a “fair share” basis. 3. Network Traffic Shaper: Ensure that critical virtual machines receive priority access to network bandwidth. Network traffic from virtual machines can be prioritized on a “fair share” basis. Network Traffic Shaper manages virtual machine network traffic to meet peak bandwidth, average bandwidth and burst size constraints. 4. Resource Pool: Aggregate collections of hardware resources virtualized by VMware ESX into unified logical resources that can be allocated to virtual machines on-demand. Resource pools increase flexibility and hardware utilization. Security: 1. Compatibility with SAN security practices: Enforce security policies with LUN zoning and LUN masking. 2. VLAN tagging: Enhance network security by tagging and filtering network traffic on VLANs. Limit the scope of broadcast domains. 3. Layer 2 network security policies: Enforce security for virtual machines at the Ethernet layer. Disallow promiscuous mode sniffing of network traffic, MAC address changes, and forged source MAC transmits. ESX VCB(VMware Consolidated backup): VCB is a group of Windows command line utilities, installed on a Windows system, that has SAN connectivity to the ESX Server VMFS file system. With VCB, you can perform file level or image level backups and restores of the VM guests, back to the VCB server. FFf Fig: ESX-VCB ESX-Vmotion: VM guests are able to move from one ESX Server to another with no downtime for the users. What is required is a shared SAN storage system between the ESX Servers and a VMotion license. Fig: ESX-Vmotion ESX at a glance: Architecture Hypervisor OS Requirements None Typical Use Cases Production, Test & Dev Dedicated Server Required Yes Centralized Management Option Yes Ease of Use High Performance Best Comparison between VMware ESX Server and VMware Server using V-Mark: Running VMmark using ESX Server on an HP DL585 with four 2.2GHz dual-core processors and then ran VMmark on VMware Server using a similar HP DL585 with four 2.4 GHz dual-core processors. The result is as below: These results show that ESX Server not only achieves higher throughput than VMware Server for a single VMmark tile (6 workload VMs) but also exhibits better scalability when a second tile is added Logs • Vmkernel – /var/log/vmkernel – records activities related to the virtual machines and ESX server. • Vmkernel Warnings – /var/log/vmkwarning – This log is a copy of everything marked as a warning or higher severity from vmkernel log. It is much easier to look through this for warnings and errors, instead of filtering through the full information in the vmkernel logs. • Vmkernel Summary – /var/log/vmksummary – Used to determine uptime and availability statistics for ESX Server; human-readable summary found in /var/log/vmksummary.txt • ESX Server host agent log – /var/log/vmware/hostd.log – Contains information on the agent that manages and configures the ESX Server host and its virtual machines (Search the file date/time stamps to find the log file it is currently outputting to). • Service Console – /var/log/messages – This log is the log from the Linux kernel (service console), which is generally only potentially useful in the case of a host hang, crash, authentication issue, or 3rd party app acting up. This log has NOTHING to do with virtual machines. The SERVICE CONSOLE (red hat kernel) has NO awareness of the VMs (worlds) running on the VMKERNEL. • Web Access – /var/log/vmware/webAccess – Records information on Web-based access to ESX Server. • Authentication log – /var/log/secure – Contains records of connections that require authentication, such as VMware daemons and actions initiated by the xinetd daemon. • VirtualCenter agent – /var/log/vmware/vpx – Contains information on the agent that communicates with VirtualCenter. • Virtual Machines – The same directory as the affected virtual machine’s configuration files; named vmware.log – Contain information when a virtual machine crashes or ends abnormally. Identify ESX Server Switch Ports Without Tracing Cables If you’ve ever had to manually trace the cables from servers to network switches in a rack you probably were not very happy about it. In fact, if you’ve ever had to trace 10 cables from each ESX host to multiple network switches you were most likely aggravated to say the least. The good news is that if you have ESX 3.5 and Cisco switches you can determine the switch ports in use via the Cisco Discovery Protocol (CDP). Even better, the VMware administrator doesn’t even need access to the network switch and can obtain the switch port information directly from the VI Client. VMware KB article 1003885 explains that CDP was introduced as of version ESX version 3.5 and provides the instructions for checking the status of CDP on the virtual switches from the Service Console. To Configure the ESX 3.5 host: 1. Log in as root to the Service Console (via SSH, remote console, or physical console). 2. Verify the current CDP setting for the desired virtual switch (vSwitch1, in this example). [root@server root]# esxcfg-vswitch -b vSwitch1 downThe output of down indicates CDP is currently not implemented To change CDP status the KB article instructs you to enter the following commands at the Service Console: 1. Set the CDP status for a given virtual switch. Possible values here are down, listen, advertise, or both. [root@server root]# esxcfg-vswitch -B both vSwitch1 2. Verify the new setting: [root@server root]# esxcfg-vswitch -b vSwitch1 both Be sure to repeat the commands for every virtual switch on the ESX host When I checked the virtual switches on one of our lab ESX 3.5 Servers I received the following output: [root@vmware01 root]# esxcfg-vswitch -b vSwitch0 listen [root@vmware01 root]# esxcfg-vswitch -b vSwitch1 listen [root@vmware01 root]# esxcfg-vswitch -b vSwitch2 listen Although the preferred configuration would be “both” so that the switch receives the CDP information from the ESX host as well, “listen” satisfies the need to use the VI Client for figuring out the switch ports in use. Now, using the VI Client you can go to the Configuration tab of a host and select Networking. To the right of each vSwitch is what I’ll describe as a dialogue icon. Clicking this icon brings up the switch port info you are seeking. In the screen shots above this is the information just for vmnic1. If you have 10 nic ports in your ESX hosts you will have to click the icons next to all your vmnics – 0 through 9. If you have a lot of ESX hosts to click through, then VMware KB Article1007069 explains how to extract the CDP information from all vnics simultaneously from the ESX Console. To extract CDP information using the ESX command line: 1. Log in into ESX 3.5 via SSH as root. 2. Run the following command on ESX command line : > vmware-vim-cmd hostsvc/net/query_networkhint 3. The following information is displayed: Virtual switch port information CDP information from the physical Cisco switch connecting to the ESX host . The following screen shot shows the same info about vnic1 from the ESX Console. The entire output of the command showed the same for all the vnics on the ESX host. Should you have access to the network switch and you’ve configured the ESX CDP status for “both” as described earlier, VMware KB article 1003885 shows an example of the commands to use to display the CDP information from the switch IOS: The following is an example of configuring CDP for a Cisco 6500 physical switch: 1. switch# 2. switch# config terminal 3. switch(config)# cdp run 4. switch(config)# interface g1/1 5. switch(config-if)# cdp enable 6. switch# show cdp neighborsCapability Codes: R – Router, T – Trans Bridge, B – Source Route Bridge S – Switch, H – Host, I – IGMP, r – Repeater, P – Phone Device ID Local Intrfce Holdtme Capability Platform Port ID pa-tse-h24.pasl.vmware.com Gig 1/1 121 S VMware ESXvmnic2 pa-tse-h24.pasl.vmware.com Gig 1/2 121 S VMware ESXvmnic3 Other bloggers have posted about enabling and using CDP in ESX. I’ve found the following posts helpful to me in the past on this topic. Identifying ESX Server NICs in Blades Next-Gen Stuff: Enabling CDP in ESX/ESXi ESX 3.5 Cisco Discovery Protocol [CDP] Support Viewing CDP Data on VMware ESX VMWare Converter Backup You will configure the backup. You will find the backup will fail what is the event ID u will get. Event ID: 57612 – Tape drive issue Event ID: 521 – VSS failure Event ID: 215 How do u troubleshoot the backup related calls Troubleshooting After installing the SP2 on windows server the server does not come up what will u do If you cannot successfully remove Windows XP SP2 by using one of the previous methods, follow these steps: 1 Insert the Windows XP startup disk in your floppy disk drive or insert the Windows XP CD in the CD drive or in the DVD drive, and then restart your computer. Note When you receive the following message, press a key to start your computer from the Windows XP CD: 2 Press any key to boot from CD Note your computer must be configured to start from the CD drive or the DVD drive. For more information about how to configure your computer to start from the CD drive or the DVD drive, see the documentation that came with your computer or contact the computer manufacturer. 3 When you receive the Welcome to Setup message, press R to start the Recovery Console. Note multiple options will appear on the screen. 4 Select the Windows XP installation in question. Note you must select a number before you press ENTER, or the computer will restart. Typically, only the 1: C:\Windows selection is available. 5 If you are prompted to type an administrator password, do so. If you do not know the administrator password, press ENTER. (Typically, the password is blank.) Note you will not be able to continue if you do not have the administrator password. 6 At the command prompt, type cd $ntservicepackuninstall$\spuninst, and then press ENTER. Note After you complete this step, you cannot stop the removal process. 7 At the command prompt, type batch spuninst.txt, and then press ENTER. Note The Spuninstal.txt file appears. As the file scrolls down, you will see errors and files being copied. This is normal behavior. 8 After Windows XP SP2 is removed, type exit, and then press ENTER. 9 Restart your computer in Safe Mode. To do this, press F8 as the computer restarts. Note After you restart, the system may lock up with a black screen. (Your mouse will work.) In this case, restart again by turning the computer off and then back on. The second restart will let you to log on. 10 When your computer restarts, Windows Explorer (Explorer.exe) does not run, and the Windows icons and the Start button are unavailable. To resolve this problem, follow these steps: a. Press CTRL+ALT+DEL to start Task Manager. b. Click File, and then click New Task (Run...). c. In the Open box, type regedit, and then click OK. d. Locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\RpcSs e. On the right side of the viewing pane, right-click Object Name, click Modify, type Local System in the Value data box, and then click OK. f. Restart your computer 2 Use one of the previous methods to remove Windows XP SP2 from your computer. Server gets crash and windows server does not come up what will u do There are different ways of server crash. One may be due to Hardware crash and the other may be due to software crash. If it’s the problem with the Hardware, it will never come up until the part is replaced. If it’s the software problem, you will receive the BSOD (Blue Screen of Death). Software problem may refer to a driver’s conflict issues, firmware issues and device driver’s issues. When any software touches the kernel mode of an OS, it will cause BSOD or Server crash. Depending upon the server functionality or the upgrades or any application installed or hardware problem, you need to resolve the issue. Service Packs

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