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 infrastructure education. 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?
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: 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.