Setting VM Attributes with vSphere PowerCLI

The vSphere annotation field is one of the most versatile tools to put basic information for the virtual machine right where it is needed most. If you are like me, you may change your mind on one or more things in your environment from time to time. Administrators can create annotations for the virtual machines, but need to be careful not to dilute the value of the annotation by creating too many values. Among the most critical attributes I like to see in the virtual machine summary is an indicator of its backup status, development or production status, or some business-specific information.

Annotating VMs

Figure 1. The annotation, in bold, is a global field for all VMs while the Notes section is per-VM. (Click image to view larger version.)

Using PowerCLI, we can make easy work of setting an annotation for all virtual machines. I'll take a relatively easy example of setting all virtual machines to have a value for the newly created ServiceCategory annotation.

For a given virtual machine inventory, let's assume that the virtual machine name indicates where it is production or some other state. If the string "PRD" exists in the name, it is a Production virtual machine; "TST" is Test and User Acceptance. Finally, "DEV" tells us it's a Development VM.

Using three quick one-liners, we can assign each virtual machine a value based on that logic:

Get-Vm -name *DEV* | Set-CustomField -Name "ServiceCategory" -Value "Development"
Get-Vm -name *PRD* | Set-CustomField -Name "ServiceCategory" -Value "Production"
Get-Vm -name *TST* | Set-CustomField -Name "ServiceCategory" -Value "Test and User Acceptance"

Implementing this in PowerCLI is also just as quick (see Fig. 2).

Taking, ahem, command of the annotation via the PowerCLI

Figure 2. The PowerCLI command will issue the annotation to multiple virtual machines in a quick iteration. (Click image to view larger version.)

Using the Get-VM command, additional features such as reading a list from a text file can be used as well as many other interpretive parameters.

Do you deploy virtual machine annotations via PowerCLI? If so, share your comments here and some of your most frequently used fields for each virtual machine.

Posted by Rick Vanover on 11/16/2010 at 12:48 PM1 comments

Religious Issue #4: Number of VMs Per Volume

I am not sure if I'm being increasingly brave here, but I'll say that I was inspired to weigh in with my comments on the contentious issue regarding the number of virtual machines per volume. It's good timing too. Recently, I just came across another great post by Scott Drummonds in his Pivot Point blog, Storage Consolidation (or: How Many VMDKs Per Volume?).

Scott probes the age-old question: how many virtual machines do we put per datastore? The catch-all answer of course is, "It depends."

One factor that I think is critical to how this question is approached and isn't entirely addressed in Scott's post is the "natural" datastore size that makes sense from the storage processor. Most storage controllers in the modular storage space have a number of options in how to determine the best size of a logical unit number (LUN) to present to the vSphere environment.

The de-facto standard is often 2 TB as a common maximum, but there are times when smaller sizes make more sense. Take into account other factors such as storage tiers, hard drive sizes, RAID levels and number of hard drives in an array; and 2 TB may not be the magic number for a datastore size. Larger storage systems can provision a LUN as a datastore across a high number of disks and can be totally abstracted from these details, making the comfortable LUN size something smaller, such as 500 GB or even less.

Scott also mentions cautioned use of a configuration command to increase the queue length for a datastore from the default value of 32. I mentioned this value in a previous post (see On the Prowl for vSphere Performance Tweaks). Like Scott, I issue caution and testing to see if it make sense for each environment. The simple example is, if there will be a small number of datastores, this command makes perfect sense. But if the vSphere environment would be highly consolidated (i.e. 60 or more virtual machines per host) across a high number of datastores (i.e. 60 or more separate datastores), the risk of the microburst phenomena may be introduced. There is no defined threshold of virtual machines or datastores, and this example (60) isn't even that extreme any more.

My general practice is to put lightweight virtual machines in the 25 or less range per 2 TB datastore for lower tiers of storage. These workloads are the basic applications that we all have and hate; yet don't really require much in terms of throughput or storage requirements. I utilize all of the good stuff such as thin provisioning and would like to always keep headroom of about 40-50 percent free space on the datastore.

For the larger virtual machines, I usually go the datastore-per-VM or datastore-per-few-VMs approach on higher tiers of storage. I'll still utilize thin provisioning, but with a smaller amount of virtual machines per datastore the free space is kept at a minimum, as usually these applications have a more defined growth requirement.

I've always thought that capacity planning (and I'd lump this into a form of capacity planning) takes a certain amount of swagger and finesse. Further, this isn't always compiled of discreet information from application requirements, storage details and a clear roadmap for growth. But we all have that clearly spelled out for us, right?

Posted by Rick Vanover on 11/09/2010 at 12:48 PM2 comments

Journey to 8 Virtual Symmetric Multiprocessors

In my virtualization journey, I frequently find storage and memory as the most contended resources. This contention is usually based around memory growth by newer OSes and everyone wants more storage that performs faster. With vSphere, we now can assign eight virtual symmetric multiprocessors (vSMP) to a single virtual machine. This is available only for the Enterprise Plus offering (see last week's post), as all other editions limit a virtual machine to four vSMP.

Straight out of the box, that means that a virtual machine can be configured with eight vSMP but not used in the most typical situation. This is presented as eight processors (sockets) at one core each. In the Windows world, we have to be careful. If the server operating system is the Standard edition, it is limited to four sockets. See the Windows 2008 edition comparison, where each edition's capabilities are highlighted. If we have a Windows Server 2008 R2 Standard edition server with eight vSMP, it will only recognize four of them within the operating system.

This means that if ESXi is installed on a host system with two sockets (with four cores each) and licensed at Enterprise Plus with a Windows Server 2008 R2 Standard edition guest virtual machine provisioned with eight vSMP, it will only see four vSMP. Flip that over, and if Windows Standard Edition is installed directly on that server without virtualization, the operating system will see all eight cores.

The solution is to install a custom value in the virtual machine configuration that presents the vSMP allocation as number of cores per socket. This is the cpuid.coresPerSocket value, and values such as two, four or eight are safe entries. Figure 1 shows this configured on a vSphere 4.1 virtual machine.

I see more than 4...

Figure 1. Adding a configuration value to the virtual machine will enable Windows Server Standard Editions to see more than four processors by presenting cores to the guest. (Click image to view larger version.)

vSphere 4.1 now supports this feature and it is explained in KB 1010184. Consider the licensing and support requirements of this value, as I can't make a broad recommendation but can say that it works. Duncan Epping (of course!) had posted about this feature last year and explained that it was an unsupported capability of the base release of vSphere. Now that it part of the mainstream offering for vSphere, it is clear to use.

From a virtual machine provisioning standpoint, I'd still recommend that this would be used exclusively on an as-needed basis. Have you used this value yet? If so, share your comments here.

Posted by Rick Vanover on 11/04/2010 at 12:48 PM7 comments

Religious Issue #5: Application Design

When it comes to providing a virtualized platform for servers, we always need to consider the application. In my experience, I’ve been on each end of the spectrum in terms of designing the application and the impact it brings to the virtualized platform.

One of the options we’ve always had is to have an application that is designed with redundancy built-in. These are the best, as you can meet so many objectives without going through major circus acts on the infrastructure side. Key considerations such as scaling, disaster recovery, separating zones of failure and test environments can be built-in if the right questions are asked. This can usually come with the help of technologies such as load balancers, virtual IP addresses or DNS finesse.

The issue becomes how clear do the benefits need to be before a robust application coupled with an agile infrastructure is a no-brainer? There is usually higher infrastructure and possibly higher application costs to design an application that can cover all of the bases on its own, yet frequently this can be done without significant complexity. Complexity is important, but the benefits of a robust application can outweigh an increase in complexity.

Whether the application be a pool of web servers spread across two sites or more involved as something that includes replicated databases with a globally distributed file content namespace, the situations will always vary but there may be options to achieve absolute nirvana. If the application is able to cover all of the bases, then the virtualized platform doesn’t become irrelevant.

The agile platform can still provide data protection, as well as on-demand scale if needed. I won’t go so far as to call it self-service, but you know what I mean. I’ve been successful in taking the time to ask these applications and dispel any myths about virtual machines (like – DR is built-in). Do you find yourself battling application designers to bake-in all of the rich features that complement the agile infrastructure? Share your comments on the application battle below.

Posted by Rick Vanover on 11/02/2010 at 12:48 PM1 comments

vSphere Folder Organization Tip

vSphere has many options for administrators to organize hosts, clusters, virtual machines and all of the supporting components of the virtualized infrastructure. I was talking with a friend about how it is always a good idea to review and reorganize the virtualized infrastructure (see Virtualization Housekeeping 101) and the topic of resource pools came up. I still find people who use a DRS resource pool as an organizational unit instead of the vSphere folder.

The DRS resource pool is not an organizational unit, but a resource allocation unit. Sure, the resource pool can be created with no reservations or limits, making no perceived impact on the available resources; but the parent-to-child pool chain is modified with the pool in place. The vSphere folder can contain datacenters, hosts, clusters, virtual machines and other folders.

The beauty of the vSphere folder is it can have its own permissions configuration. By default, it inherits the permissions from the parent; but it can be configured for explicit permissions. Fig. 1 shows a folder of Web servers and the ability to assign permissions for that collection of virtual machines.

vSphere Folders

Figure 1. Permissions can be extended to folders to function as containers for roles or simply organizing virtual machines. (Click image to view larger version.)

I find myself using the permissions of a folder to function like a group membership assignment that follows in the Active Directory world. The role functionality of vSphere allows the administrator to delegate a lot to different categories of users of a virtual machine. This can be as simple as view the virtual machine console, allow virtual media mount capabilities or even the virtual power button.

Do you use the folder for organization or permissions? If so, share how you use it here.

Posted by Rick Vanover on 10/28/2010 at 12:48 PM1 comments

Sub-$500 VDI: Not Just From the Big Boys

Anyone who has tried to go down the VDI path for a small client virtualization installation and came to a hard stop will welcome any arrangement that makes it easy. VDI is a tough technology to reign in compared to the great success we've had in virtualizing servers. Many situations can bring a VDI effort to a stop, including a cost model that still puts physical PCs as the ROI winner.

At VMworld, one product that caught my eye is Kaviza's VDI-in-a-box. Simply put, Kaviza makes a broker that works pretty much anywhere to anywhere. The current offering includes support for XenServer and VMware hypervisors, with Hyper-V support coming. The endpoint can be anything from a PC client install (bring your own computer to work anyone?) to native RDP and Citrix HDX support for use on a number of thin-client devices such as Wyse and 10ZiG devices.

I noticed a few things from running the demo. For one thing, VDI-in-a-box can utilize direct attached storage. I've long thought that DAS has a use case in virtualization to some extent, as the cost savings can be so great that a shared storage infrastructure may not be required. Of course, many factors go into any decision; but DAS can be high-performance and eight drives or more can be on a local array.

The Kaviza solution utilizes a virtual appliance on each hypervisor to broker the connections to a wide array of supported endpoints (see Fig. 1).

Kaviza VDI-in-a-box

Figure 1. Kaviza's VDI-in-a-box builds on commodity components (in green) and provides the broker as a virtual appliance and uses a supported protocol to bring a VDI session to a number of devices. (Click image to view larger version.)

The best part of the Kaviza solution is that it can run under $500. This includes the server, hypervisor, Kaviza ($125 per concurrent user) and Microsoft costs. This cost does not include the device if a non-PC is used; on the high-end the street price would be $425 per client with Kaviza's online ROI guide.

Does a sub-$500 VDI solution not offered by VMware, Citrix or Microsoft appeal to you? Share your comments here.

Posted by Rick Vanover on 10/26/2010 at 12:48 PM2 comments

vSphere Decisions: Enterprise vs. Enterprise Plus

When vSphere was first released, the new features and their alignment to existing investments created lots of confusion. Customers that have an active Support and Subscription (SnS) agreement were entitled to a certain level of vSphere features. There were no direct mappings to the Enterprise Plus level of vSphere that did not involve the promotional pricing to upgrade all processors to Enterprise Plus, however.

At the time, the Enterprise level of vSphere licensing was slated to be available for sale for a limited time. To this day, Enterprise is still available for sale. For anyone considering between the two versions, I will definitely nudge you towards Enterprise Plus. Here are a few reasons why:

  • vSMP support: Enterprise currently limits a virtual machine to 4 vCPU, effectively still functioning at the same level as ESXi 3.x. vSphere is capable of 8 vSMP to a single virtual machine, but it isn't licensed to that level unless Enterprise Plus is utilized.
  • Cores per processor: Enterprise limits this to six cores per socket. While the current mainstream processors are available with six cores and will easily fit most installations, consider the future and any licensing that will be reapplied to new servers.
  • Distributed switch functionality: This is somewhat forward-looking, but if at any point vCloud Director would be a consideration in the future; this is made much easier with the heavy networking investment.
  • Host profiles: This vSphere feature allows customized host configurations for almost any manageable value to be applied centrally to vCenter after a host ESXi system is installed.

The full breakdown of Standard, Advanced, Enterprise and Enterprise Plus licensing levels is here.

The other side of the coin is, if all of these levels bring too much cost into the picture and the features are not required, VMware has made a serious leap forward with the revised Essentials Plus offering. Basically, small and remote sites that need a virtualized infrastructure will see it as a winning solution; but not all of the features of the big datacenters. Check out the Essentials Plus offering here.

Enterprise Plus may not be needed for all installations, but if the decision rests between Enterprise and Enterprise Plus; it should be pretty clear which way to go.

Have you made the case to stay on Enterprise? If so, share your comments here.

Posted by Rick Vanover on 10/21/2010 at 12:48 PM5 comments

VMware Standalone Converter Updated

During VMworld in San Francisco, an important update crept out for the VMware vCenter Converter Standalone edition. It was great news for me, as I had started to wonder if the product was going the way of a deprecated product. The virtual machine conversion mechanism is still an important part of the arsenal for today's virtualization administrator. I frequently use it for additional physical-to-virtual conversions, specialized virtual-to-virtual operations such as a data center migration and to shrink existing virtual machines.

Version 4.3 was released on August 30 with two key features. The first is support for Windows 7 x86 and x64 editions; the other is support for Windows Server 2008 x86, x64 and R2 editions. This support is both for a machine to be converted as well as the platform to run VMware Converter. After installing VMware Converter 4.3, the supported operating system table only goes as old as Windows XP for Windows systems. This means that Windows 2000 has fallen off of the supported platform list for Converter 4.3. It may be a good idea to grab one of the older copies of VMware Converter while you can, in case you still support Windows 2000.

VMware Converter 4.3 adds a number of other natural platform support configurations, including support for vSphere 4.1. But perhaps the most intriguing support with this release is a broad offering of Hyper-V support. Windows virtual machines that are powered on while running on Hyper-V may be converted as well as powered-off virtual machines that run Windows Server 2008 including x86, x64 and R2 editions, Windows 7, Windows Vista, XP, SUSE Linux 10 and 11, and Red Hat Enterprise Linux 5. Microsoft .VHD and .VMC virtual disk formats can also be imported.

I've used it a few times since it was released and have not had any issues with it performing virtual-to-virtual conversion tasks. VMware Converter is still a critical part of the daily administrator's toolkit and finally made complete with Windows 7 and Server 2008 support.

Have you had any issues with the new version thus far? Share your comments here.

Posted by Rick Vanover on 10/19/2010 at 12:48 PM5 comments

VMworlds Scheduled Close Together -- The Right Move

One of the things I love about virtualization is that the virtualization community aspect is so well defined. I particularly enjoy also that the VMworld events are a manifestation of the community, and that was repeated this week in Copenhagen for the VMworld Europe show. In years past, VMworld Europe has been at a polar opposite on the calendar from the VMworld event in the U.S.; which finished up in early September in San Francisco.

By having the events so close together, VMware and the partners can control timing of news as well as releases. It is an incredible feat to pull off an event the size of VMworld, much less having to repeat the ordeal a mere six weeks later in Europe. By having the same message, announcements, labs and other components that make up VMworld; there is an incredible logistic efficiency obtained.

After VMworld in San Francisco, I had a discussion about the logistics of one, two or even three events recently on the Virtumania podcast. A suggestion was raised to have more events, and I quickly chirped in saying that it is way too much work to put on an additional event of this level. This leads to my biggest complaint about VMworld, the fact that the US events are always in the Western part of the country. There are plenty of destinations in the central part of the US, but the most compelling reason is for the attendees. Given that there is not a VMworld for the Asia/Pacific region, a VMworld event needs to be accessible for those attendees. The Western cities of San Francisco, Las Vegas, Los Angeles and others do that nicely.

For my own VMworld attendance strategy, next year I am going to try to attend both events. This will allow me to fully take in everything that you miss between the two events. Believe me, there is plenty to take in. If you are borderline on attending VMworld and have never done so before, I recommend you do it. There is something for everyone at the event, and as a blogger I find this as an important way to meet up with other bloggers, tech companies and the readers.

Until next year, the craze that is VMworld will get quiet. As for the whole cloud thing, well, we'll work on that.

Posted by Rick Vanover on 10/14/2010 at 12:48 PM2 comments

Virtualization Housecleaning 101

What's great about virtualization is the fact that we can change just about anything we want with minimal impact to production workloads. It's partly due to functionality from hypervisors and management software, but the human factor plays a big part. Here is a quick housecleaning checklist to review through a vSphere environment (and applies to versions of vSphere and VI3), to catch the small things that may have accumulated over the years:

Datastore contents: How many times have you put a powered-off virtual machine in a special folder, on a special datastore or held onto just a .VMDK in case you ever needed it? There are a number of crafty ways to find these, including using a product like the VKernel Optimization Pack to find unused virtual machines. Also keep your eyes open for the “Non-VI workload” error message from last week's blog post.

Reformat VMFS: I know there is no hard reason to upgrade, but it is annoying to see a smattering of volumes that are created as storage is added and ESXi (or ESX) versions are incremented. Evacuating each volume with Storage vMotion and reformatting will bring every volume up to VMFS 3.46 (assuming version vSphere 4.1 is in use). This would also be a good time to reformat each volume at the 8 MB page size, as there is no real compelling reason to be on 4, 2 or 1 MB sizes.

Check for antiquated DRS configuration items: Rules that are not needed any more, resource reservations that were a temporary fix, or limits that may not need to be in place can put extra strain on the DRS algorithm.

Reconfigure drive arrays: If you have been wishing to reformat a drive array at a different RAID level (such as RAID 6 instead of RAID 5), the previous datastore step may create a good time to correct this.

Reconcile all virtual machines with lifecycle and approval: We've never stood up a test virtual machine as an experiment, have we? Make sure all experimental machines are removed or that they still need to exist.

Permission and role reconciliation: Check that the current roles, active administrators, permissions and group setup are as expected.

Template and .ISO file cleanup: Do we really still need all of the Windows 2000 and XP virtual machine templates? Chances are at least one template can be removed.

Update templates: For Windows updates, VMware Tools, virtual machine version, etc.; these configuration elements can quickly get obsolete.

Change root password: Probably a good idea if you've had staff turnover at some point.

Do you have any additional housekeeping items? Share your periodic tasks here.

Posted by Rick Vanover on 10/12/2010 at 12:48 PM5 comments

Fault-Tolerant Options Expand with everRun MX

One of the pillars of virtualization is the ability to abstract servers from hardware to provide additional availability. Of course, infrastructure demands continue to increase and we seek to deliver high availability or even fault tolerance beyond the basic virtual machine. A number of solutions are available for virtual workloads.

The fault-tolerant space has three mainstream players: the VMware Fault Tolerance virtual machine feature with vSphere, Neverfail (which has an OEM relationship for VMware's vCenter Server Heartbeat feature) and Marathon Technologies. Neverfail aligns with VMware, and Marathon aligns with Citrix.

Since the middle of the last decade, Marathon Technologies has offered solutions from HA to FT for Windows workloads before virtualized servers were mainstream in the datacenter. Back when I worked in the supply chain software industry, I used the everRun HA solution to replace fault-tolerant hardware solutions such as the NEC Express5800/ft or Stratus ftServer. Even back then, Marathon allowed customers to utilize commodity hardware for these HA and FT solutions.

Marathon recently released everRun MX, which provides a flexible offering to deliver FT workloads on commodity hardware. everRun MX can work for those who want to deploy a robust solution for a few workloads without a huge investment. everRun MX can use direct-attached storage or shared storage, making it price competitive if a traditional SAN is not involved. I've always thought it is very tough to provide a robust, highly available virtualized environment from small footprints such as a remote office.

With everRun MX, a base configuration starts at $10,000 and allows administrators to run a pair of servers of any configuration (core/sockets/memory) and includes one year of support and maintenance. The servers must have Intel processors. You can run everRun MX on dissimilar hardware, but they should be comparable. everRun MX uses the term Metal Pool, which would loosely equate to a cluster of virtual machines running with FT capabilities.

everRun MX

Figure 1. everRun MX allows a collection of virtual machines to function in a fault tolerant mode on commodity hardware. (Click image to view larger version.)

You might be asking: How well would this type of configuration be received within the greater software landscape? As virtualization customers, we go through this battle with new software titles to see if the software vendor supports their product being run on a virtual machine. For an architecture like this, it's not as widely embraced as is a VMware virtual machine as a supported platform. But Marathon does offer 24x7 worldwide support in addition to an extensive partner ecosystem. I haven't used Marathon products in a while, but everRun MX seems to bring more to the table for the customer seeking value and features.

Let me know if you want to see more of everRun MX and I'll follow up with an evaluation!

Posted by Rick Vanover on 10/07/2010 at 12:48 PM7 comments

Somewhat Uninformative vSphere Alert

In VMware Infrastructure 3, the one area that the vCenter Server needed to do a better job was its built-in alarms and alerting. So, one vSphere 4 objective was to increase the breadth of built-in alarms. This saves administrators time with PowerShell, as the only way to achieve full safety is to script alerts and send e-mails.

The good side is that you can put in a lot of handling and specific criteria for the thresholds -- well, at least as good as you can script them. The bad side is that the vCenter Server database doesn't track these events to the affected object (datastore, host, VM, etc.).

vSphere 4 has a new alert, "Non-VI workload detected on the datastore" that is somewhat misleading. This message shows up on an otherwise healthy datastore (see Fig. 1).

The basic premise for this alert on the datastore is to avoid a virtual machine that is removed from inventory consuming too much space on the datastore. This is somewhat of a misnomer, as many administrators put non-workload data on datastores. This data can include CD-ROM .ISO files as well as a special backup of a system before it is deleted.

Further, the VMFS file system has built-in functionality to allow multiple ESXi hosts connect. This means that you can have a number of ESXi hosts that may be licensed with vCenter connect to a datastore, and that same datastore is zoned on the storage system to another ESXi system, such as the free edition without vCenter (I cover this in my "Forward Motion" post from last year).

The new alert is also somewhat useless as it doesn't tell you what the offending workload is on the datastore. Administrators are left to use the Storage View functionality and maps to determine what files or virtual machines are the culprits. I'm all for saving datastore space, but I don't like that this defaults to an "Alert" level and issues a red indicator. This can be changed to a "Warning" level and issue a yellow indicator in the definition of the alarm (see Fig. 2).

Foreign Content Alert! Foreign Content Alert!

Figure 1. While the datastore has ample space and adequate connectivity, an alarm is generated by the presence of foreign content. (Click image to view larger version.)

Warning, not alert

Figure 2. You can make this condition issue a warning instead of an alert in the definition of the alarm. (Click image to view larger version.)

Do you find this alert a little confusing or over-cautious? Share your comments here.

Posted by Rick Vanover on 10/05/2010 at 12:48 PM1 comments