Submitted Michel Roth

Quest just launched a new free tool on the vWorkspace Community called the vWorkspace Desktop Optimizer. It is important to note that this tool not only works for Quest vWorkspace but also works for other desktop virtualization product like Citrix XenDesktop and VMware View or other.

Tests have shown that the impact of the vWorkspace Desktop Optimizer can be quite big.

VDI performance -  vWorkspace Desktop Optimizer

As you can see the big savings are in the area of storage. Because of the optimizations applied to an idle (so no user logged on) Windows 7 Enterprise VM by the Quest vWorkspace Desktop Optimizer the read and write IOPS were reduced by more than 90%. This has a huge effect on the scalability of VDI environments since (lack of) IOPS is currently the most common bottleneck in VDI deployments.

There are also disk space savings. We deployed two virtual desktops via the Quest vWorkspace rapid provisioning options (Differencing Disks / Linked Clones) and then we compared the vanilla Windows 7 virtual desktop to the virtual desktop optimized with the Quest vWorkspace Desktop Optimizer. The virtual desktop optimized with the Quest vWorkspace Desktop Optimizer consumed 43% less disk space.

In addition, the Quest vWorkspace Desktop Optimizer also introduced RAM savings of up to 10%. Some people have seen more savings, up to 200 MB per virtual desktop but this depends heavily on the characteristics of the virtual desktop.  Finally, a virtual desktop optimized by Quest vWorkspace Desktop Optimizer also consumed up to 37% less CPU although it has to be stated that this was measured on (as stated earlier) a desktop with no users logged on so even though the relative savings are high, the absolute savings are not that dramatic.

The vWorkspace Desktop Optimizer is a collection of 40 optimizations to Windows to make them more ‘VDI friendly’. VDI friendly in this case primarily means that it will consume less system resources and thus improve the resulting scalability of the VDI environments. The vWorkspace Desktop Optimizer provides the capability to filter optimizations based on ‘impact’ allowing you only to apply those optimizations. It also allows you to filter by category so you can see to which area the optimizations apply with the categories being Storage, CPU&Memory and User Experience.

Quest vWorkspace Desktop Optimizer

Next to the main UI the vWorkspace Desktop Optimizer also accepts command line switches. One switch, the –edit switch, allows you to open up to UI so you can change the description and justification fields using the editor. The other switch is the –run switch. This will allow you to run the vWorkspace Desktop Optimizer from the command line so you can use the vWorkspace Desktop Optimizer in scripts.

The final feature I would like to put out is the ‘Export’ function. This allows you to export your current vWorkspace Desktop Optimizer configuration to an formatted XML file for easy use in your documentation efforts.

Quest vWorkspace Desktop Optimizer – Export

If it wasn’t clear, the vWorkspace Desktop Optimizer is completely free, directly available from the vWorkspace Community. All feedback is welcome as next version of the vWorkspace Desktop Optimizer will be built based on suggestions from the community.

vWorkspace Desktop Optimizer

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There are some key differences in how SCVMM 2012 integrates with VMware’s infrastructure compared to SCVMM 2008. It no longer imports, merges or synchronizes the tree structure from vCenter to SCVMM, instead you manually add ESX servers to any VMM host group.

Integrating SCVMM 2012 with VMware’s platform

When you import a VMware template to the library the .vmdk file is left in the ESX data store and only the metadata is copied to the library. HTTPS is used for all data transfers between ESX hosts and the VMM library which means there’s no longer the need to enable root Secure Shell (SSH) access to ESX hosts to support the Secure File Transfer Protocol (SFTP).

SCVMM Services can be deployed to ESX hosts but they’re not compatible with VMware vApps, likewise ESX hosts resources can underlie a SCVMM private cloud but it’s not compatible with vCloud. SCVMM supports up to 8 virtual CPUs for VMs on ESX/ESXi 4.0 hosts and up to 255 GB of memory and also recognises VMware fault tolerant machines.

Integrating SCVMM 2012 with Citrix XenServer

Unlike VMware, XenServer hosts and pools are managed directly from SCVMM 2012 so there’s no reliance on the XenCenter server. Migrations are supported through Citrix XenMotion, the equivalent of Hyper-V Live Migration. Both hypervisor and paravirtualization in XenServer is supported. If you have XenServer vhd files stored in the library set the virtualization platform to XenServer to distinguish them from Hyper-V vhd files.

Small catches to be aware of in this beta is that your hostnames have to match exactly (including case) to the self-signed certificates that XenServer creates and all the different virtual network switches that XenServer creates are represented as one switch inside of SCVMM.

Patching cluster hosts in SCVMM 2012

One of the trickier things to manage in a clustered environment is updating the hosts. While management platforms such as Systems Center Configuration Manager can do it they’re not cluster / virtualization aware and are likely to push out patches to all hosts simultaneously, causing an outage as they all reboot. SCVMM works around the issue by integration with a dedicated 64 bit WSUS 3.0 SP2 server and orchestrating cluster patching by Live migrating VMs to other nodes, patching and rebooting the host, moving VMs back and the repeating the process on the next cluster node. The actual patch requirements are determined by Update Baselines which specify which patches are required on hosts, library servers, PXE servers and the SCVMM management server itself. Once you have assigned a baseline to a group of computers they’re scanned to determine if they’re out of compliance and patching can then take place to make them compliant. There’s also an option for exemptions if a particular patch is causing issues on one or more hosts.

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If you are using any of the snapshot-based backup solutions for your virtualized machines—Veeam Backup & Replication and vRanger being the two most popular—then from time to time you are probably going to see a failed backup. This is a common occurrence even with traditional backup solutions, but in this situation it can have a drastic effect on your production environment.

While I can only directly speak for the effect with Veeam, as it is the only one I’ve used, the situation described here as I understand it is common to all of the VMware-centric backup systems. What happens is specific to situations where bandwidth is constrained, like when you are replicating over the WAN to off site. Backup job A runs and successfully completes. The last stage of the backup process is removing the temporary snapshot that is used to create the backup; this can be a time-intensive process depending on how large the backup (and thus the snapshot) is. During this process, backup job B attempts to create a snapshot and begins backing up the same virtual machine. When this happens, the VMware helper that was trying to merge the original snapshot (<disk>-delta.vmdk) back into the disk file (.vmdk) becomes orphaned. Furthermore, VMware still believes the snapshot to be locked by the original process.

In my experience, there are four steps to troubleshooting this issue and getting the delta files to roll back up into the disk files. You hopefully will not have to complete all four, as they are steps for “this fix isn’t working.” The first two can be done on a running VM, so you incur no downtime; the second two require you to take down the VM.

Step 1: Unlock the snapshot

The first step is to get the snapshot unlocked. The trick to this is to migrate the VM from the host it is on to another and then back again. Those of you using a vCenter-based infrastructure should know all about this. Just vMotion the machine, not the datastore, from one host to another.

It is important to vMotion the machine back to the original host. If you don’t, you get introduced to another error. Once the process is finished, you should be able to go into Snapshot Manager and click the “Delete All” button to clear them all out. Don’t be alarmed if the process of “Remove all snapshots” seems to hang on 95%; this is normal operation and, depending on the size and quantity of the snapshots, this process can take many, many hours.

Step 2: Trick vCenter

In some cases, after you perform the migration and you open Snapshot Manager, it appears that the VM has magically gotten rid of all of its snapshots. If you browse the datastore where the VM resides, using either the GUI VI Client or the CLI via SSH, you will still see the delta files there. If this is the case, you can trick vCenter into showing you the snapshots again by creating another snapshot manually (right-click VM, choose snapshot, “Take Snapshot”). When done, all of your Consolidate Helpers will reappear. After that, try to Delete All from the Snapshot Manager again.

Step 3: Migrate the datastore

If you have gotten to this point, I hate to tell you but you are now looking at some down time from here on out. If the snapshots still haven’t moved, the next step in my process is to shut down the virtual machine and migrate the datastore. Yes, I know, you are probably screaming at the screen about the fact that, with ESX 4, you don’t have to shut down to migrate the data any more. However, if you have reached this step, there are most likely more delta files than the VI client could handle before reaching the timeout limit, and shutting down makes the process faster and more robust. Migrating the datastore will have the effect of rolling the deltas back up if the process completes successfully.

Step 4: Convert the virtual machine

This step is for those of you (myself included) who ignore the problem too long. ESX is only capable of handling 32 snapshots for any given VM. Beyond that, trying to Delete All will not work. Neither will migrating the datastore. In this case, you need to install VMware’s standalone Converter tool on the VM and perform what’s referred to as a v2v, or virtual to virtual, conversion. I’ve seen reference to just using the VI client to clone the VM, but this process was defined to me by VMware support, so I’ll trust their judgment.

I have only reached this step once, and I hope to avoid it from here on. Current Windows activation will not survive this process, so at the least you will have to reactivate. At worst, you might actually have to call Microsoft and have them manually activate your server.

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We recently purchased some new Intel X520-t2 cards for our existing VMware ESX 4.1 hosts. The card has two ports, each capable of transmitting ten Gbps each.

Unfortunately, the driver for this card isn’t in the default set installed with VMware vSphere. Like all things VMware, getting these to work in an existing host is not the easiest of things. During ESX installation, a big glaring warning message is displayed: “If you choose to not install additional drivers at this time, you will not be able to do so later.” Well, that’s not exactly true. To work around this, just follow the instructions below.

1. Verify that the card is supported by the VMware HCL.
2. Download the driver from VMware’s Driver CD Repository.
3. Put your ESX/ESXi host into maintenance mode.

At this point, you can install additional drivers one of two ways: via the vSphere CLI, where you run the files from your own workstation, or via the esxupdate command on the ESX host itself. I personally prefer to do it directly from the ESX host as that’s one less variable to flub up.

Install the driver from the VMware ESX host itself

Upload your downloaded ISO to the ESX Service Console using an SFTP client such as Filezilla. I generally just put it in my home directory.

1. From the console of the host, or via SSH connection, mount the ISO using the command mount -o loop -t iso9660 <isofilename> /mnt/cdrom/
2. Use the esxupdate command to install the driver. On any driver CD you download from VMware is a folder called “offline-bundle,” within which is a zip file. This is the actual driver execution package. So to install a driver called driver.zip, your command should look like this: esxupdate –bundle=/mnt/cdrom/offline-bundle/driver.zip update
3. Once the command executes successfully, reboot your host. This can be done via the CLI by typing “reboot“.

Install via the VMware vSphere CLI from your local ESX/ESXi host

1. If you haven’t already installed the vSphere CLI, you can get it at VMware.

2. Burn the downloaded ISO to a CD and leave it inserted in your drive.

3. Open a command prompt at “C:\Program Files (x86)\VMware\VMware vSphere CLI\bin” (assuming you are using an x64 flavor of Windows).

4. Use the vihostupdate Perl script as shown: vihostupdate.pl –server <IP Address of host> -username root –install –bundle <path to offline bundle> The “path to offline bundle” is much like what was used in the other option, but it just looks at your local drive. An example would be “D:\offline-bundle\driver.zip”.

5. Reboot. You can choose the “Reboot” option in the VI Client to do this.

That’s it! After you reboot, you should be able to see your new device in the Configuration area of your host. Below are before and after images of my test host.

Jim Jones is a Senior Network Administrator with a West Virginia state agency but has worked in the automotive manufacturing and academic arenas as well.  He has over ten years of experience in IT with emphasis on Microsoft, Cisco and VMware infrastructures.

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This past July, version 4.1 of VMWare’s vSphere enterprise virtualization platform was released. Among the patches and performance fixes (full list of new features here) support, Active Directory administrative authentication was added.

So why would you want to do this? After completing the process described here, authentication will be centralized and you will have control over access to the ESX hosts much in the same way you do any other Windows server or desktop.

The only caveat regarding this procedure depends on how you are handling your Windows Server Client Access Licenses, or CALs. Because your ESX/ESXi hosts will be added to Active Directory, if you are using a Device CAL licensing model, these servers would each require a CAL. Most enterprises I’ve seen tend to lean towards the User CAL method, so in that case this would be a nonissue. For more information this is covered in greater depth by Rick Vanover over at Virtualization Review.

The first step of enabling this feature is to create a security group in your Active Directory named “ESX Admins.” You must use this exact name or the process doesn’t work. Once created populate this group with the users you wish to have the capability to manage your ESX hosts. For smaller shops you can cheat by just adding the Domain Admins group.

Next you need to go ahead and open your VMware VI Client. Before joining our servers to the domain first we need to verify that DNS and NTP are both configured properly, pointing both back to the sources for your Windows Active Directory infrastructure.

Now in the left menu, click the host you want to add to AD, and then click on the configuration tab. Once in configuration, choose “Authentication Services” from the Software submenu. Once there first notice that the current Directory Services type is Local Authentication, meaning it is using the local user groups.

To join the host to the domain, you need to click the Properties link in the top right corner, launching the Directory Services Configuration dialog. At this point it should feel much like joining a workstation to the domain. Set the Directory Service type to Active Directory and supply your domain name, making sure you use the FQDN rather than the NetBIOS version. Now when you click “Join Domain”, you will be prompted for Active Directory credentials capable of writing to AD. Finally, click Join Domain again and you’re done!

As you can see above, once completed, the VI Client will report that it is joined to the domain and authenticating to the domain. Looking further in to the Active Directory of Users and Computers, the host will be shown with a computer account in the directory.

The end result: Your IT staff and other users who access Virtual Machines can now use your centrally managed Active Directory credentials to authenticate to ESX or ESXi. This greatly enhances the security of the system because it makes password policy much more enforceable and the staff will be happy because it is one less password that needs to be memorized.

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• Microsoft Hyper-V Dynamic Memory vs. VMware Memory Overcommit (5)

In an attempt to provide higher levels of server consolidation, both Microsoft and VMware have developed their own solution for higher utilization of Random Access Memory (RAM). VMware’s Memory Overcommit has been available for quite some time, while Dynamic Memory is a new player. How do they compare?

It is always hard to make comparisons like this one. I don’t want to start a fight between VMware’s and Microsoft’s fan-boys. In my view, it is too early to say which memory management technology is better. In this article, I will just compare both approaches.

VMware Memory Overcommit

I have always been amazed by VMware’s success with the Memory Overcommit technique, and the ability to provide more RAM to virtual machines than a physical computer actually has. I’m sure many system administrators use this feature in their organizations. It works on a very basic principles:

1. Give more memory to virtual machines than a physical computer has.

2. Identify the same memory blocks (by hash) in multiple virtual machines.

3. Compress the host memory by storing those blocks only once.

This is accomplished by External Page Sharing or Second Level Paging technique, which I won’t describe in detail here. It is important to note that VMware does not trust the information from the guest OS. Memory is assigned to virtual machines based on the information that is available on the level of the host OS. This makes sense because of security and stability reasons.

Microsoft Hyper-V Dynamic Memory

Hyper-V Dynamic Memory works different. Instead of compressing the host RAM, it allows virtual machines to demand more RAM if required. This works similar as with dynamic virtual disks. System administrators have to configure a startup (minimum) and a maximum amount of memory for each virtual machine. The sum of all maximum values can be larger than the total amount of memory on a physical server. Microsoft calls this Memory Oversubscription. However, the sum of all amounts of memory given to each virtual machine will never exceed the limits of a physical computer.

To use Dynamic Memory for Hyper-V, you have to install Service Pack 1 for Windows Server 2008 R2 which is still in beta. If you install the Integration Components in the guest OS, a small driver called Dynamic Memory Virtual Service Consumer (DM VSC) will monitor the memory usage in the guest OS. This driver collects information about current RAM requirements and reports it to the host which decides to give or take RAM from the virtual machine.

Hyper-V Dynamic Memory vs. VMware Memory Overcommit

It is too early to give a final judgment which technology is more effective. Microsoft virtualization team has a huge advantage for being able to work with the Windows kernel team (Linux distributions are not supported, yet, but it might change in future), and use information from the Windows kernel to calculate the current memory needs of a virtual machine.

However, Hyper-V Dynamic Memory still has to prove its efficiency in real world scenarios. Windows Server 2008 SP1 is still in beta, while VMware Memory Overcommit has been working reliably in enterprise environments for a long time. What’s your experience? Which technology do you prefer?

Ilija Brajkovic is a system administrator and MVP (Microsoft Most Valuable Professional) for the Virtual Machine expertise. He runs the Windows Server 2008 and Microsoft virtualization blog.

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This initial release includes the ability to backup, restore and update your ESXi host (epically handy for people that are not using VirtualCenters Update Mangers).

VMware RCLI is required to be installed on your machine in order to use the ESXi Configurator Utility.

I have been using this tool for some time now , and it’s working great , I would really recommend it !

ESXi Configurator Utility

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Greg Shields published an interesting article that explains the difference between the hypervisors of Microsoft’s Hyper-V and VMware’s ESX. It is a response to a widespread misunderstanding. VMware supporters tend to believe that VMware ESX has a bare metal hypervisor, whereas Hyper-V runs like Microsoft Virtual Server 2005 on top of Windows. Greg explains in detail in what sense both virtualization solutions are Type 1 hypervisors contrary to Virtual Server and VMware Server, which use Type 2 hypervisors. A Type 2 hypervisor is installed on top of the administrative OS, whereas a Type 1 hypervisor runs on bare metal, a layer below the administrative OS (Windows Server 2008 in the case of Hyper-V and Red Hat in the case of ESX).

However, there are also important differences between Hyper-V’s and ESX’s hypervisors. Greg makes things absolutely clear: Hyper-V has a far more advanced hypervisor because it is microkernalized, whereas ESX has a monolithic hypervisor. Among other things this means that Hyper-V uses synthetic device drivers, which are just pointers to the real device drivers into the primary partition’s administrative OS (Windows Server 2008). ESX’s device drivers exist within its hypervisor. Hyper-V’s architecture has quite a few advantages:

• Hyper-V’s smaller microkernel improves performance
• Hyper-V supports paravirtualization, which improves the performance of supported guest operating systems
• ESX monolithic hypervisor leverages hardware emulation, which makes it slower
• ESX’s kernel has a higher complexity, which makes it more prone to errors
• Supporting new devices is more time consuming for VMware because drivers have to be integrated into the kernel
• Hyper-V supports more devices because it relies on Windows devices drivers

The fact that Hyper-V’s administrative OS in the parent partition is a full-blown Windows Server 2008 installation and therefore is much bigger than in ESX’s case is no disadvantage because disk space is not an issue these days. The mere size of the parent partition has no negative effect on the hypervisor’s performance.

This is certainly true, but I’d like to add that the mere presence of all this Windows code in the parent partition increases the attack surface. Considering that Windows is more widespread than Linux, ESX is probably the more secure virtualization solution. Furthermore, Hyper-V’s reliability depends more on third party device drivers.

Greg acknowledges that Hyper-V plus Virtual Machine Manager lack some important management features compared to ESX and Virtual Center. I think there is still a long way to go for Microsoft to catch up with VMware in this area. However, Microsoft is already ahead as far as the hypervisor, which is the core of any server virtualization solution, is concerned.

Please check out Greg’s article about the differences between hypervisors of Hyper-V an ESX, which outlines the arguments in much more detail.

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The free Vmdk2Vhd tool can help you convert a VHD image into VMDK format. Note that it is recommended to convert a big VMDK file to multiple 2GB VMDK spanned files first. Jérôme Laban has described some other issues you might encounter.

Converting the virtual disk alone is not the only problem you will face if you want to migrate virtual machines from a VMware ESX or VMware Server to Hyper-V. It is like moving a hard disk from one computer to another or using the same OS image on different hardware. Virtual machines are not that much different than physical computers. Thanks to Windows Vista’s and Server 2008’s new imaging capabilities, it should always be possible to move virtual machines from one virtualization environment to another.

It might also work with Windows Server 2003 and Windows XP, but I would recommend using a more professional tool to convert virtual machines with these operating systems. I have used Microsoft’s Virtual Machine Manager 2008 (VMM 2008) to convert VMware machines to Hyper-V and it has always worked reliably. VMM 2008 is not free, but you can download a 180-day trial. I suppose that’s enough time to convert all your VMware machines.

Have you migrated virtual machines from VMware to Hyper-V or Virtual Server? If so, it would be nice if you shared your experiences.

Vmdk2Vhd

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When you first launch the VMware DiskMount GUI, you have to tell the tool where to find vmware-mount.exe. If you installed VMware’s toolkit in the default folder, then you can find it under C:\Program Files\VMware\VMware Virtual Disk Development Kit\bin\. The DiskMount GUI supports all of DiskMount’s command line parameters, including those for remote virtual disks (ESX Server and VirtualCenter).

If you just want to mount a local VMDK file, it’s not necessary to fill out all the parameters in the “Mount Virtual Disk” tab. The ones you do need to fill out are marked in this screenshot.

If the virtual disk has snapshots, you will always have to mount the latest one. You’ll find multiple consecutively numbered VMDK files in the virtual machine’s folder. Mount the VMDK file with the highest number. If you try to mount another VMDK file you will receive a “mount error” message. Note that if you make changes to the virtual disk, and then revert to a snapshot, you will lose all of your changes.

The VMware DiskMount GUI appears to have an option for overriding this snapshot setting. However, when I tried the feature, vmware-mount.exe just answered with a list of available parameters. My guess is that older versions of VMware DiskMount supported this feature, but newer ones do not.

If you have never worked with VMware DiskMount, you might want to have a look at the manual first. It appears as a PDF file in the doc folder. It explains all of the parameters in detail, and gives you some information on how to use DiskMount. The most relevant details are:

• You can mount virtual disks created by VMware ESX Server 3.x and 2.x (pre-allocated disks only), VMware Workstation 6.5 and 4, VMware Player, VMware ACE, VMware Fusion, VMware Server, and VMware GSX Server 3.x and 2.5. I also was able to mount virtual disks created by earlier VMware versions.
• You can’t mount a virtual disk that is currently being used by a running or suspended virtual machine.
• You can’t mount a virtual disk if any of its .vmdk files are compressed or have read‐only permissions.
• You can only mount FAT (12/16/32) or NTFS volumes on a Windows host. It is possible to mount a Linux file system, but once the virtual disk is mounted as a drive letter, Windows will try to format the new disk, which probably isn’t a good idea. If you want to mount a Linux virtual disk you need a Linux host.

Update: The tool appears to be no longer available. Please drop me a note if you know where it can be downloaded.

VMware DiskMount GUI

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When I first tried VirtualBox I thought it was not much different than Virtual PC. Only when I used it for a while did I find out that it has some essential features that Virtual PC lacks, as described below:

Multiple snapshots

One of the biggest advantages of running software tests in a virtual environment is that you can create a snapshot of a stable configuration which allows you to go back to that point in time if you mess up your system. Virtual PC 2007 SP1 has an undo function which can be considered as a single snapshot. VirtualBox supports multiple snapshots. This way, you can save states of your virtual machines the same way you store different versions of a text document. You can also create snapshots while the virtual machine is running. Virtualbox’s snapshot feature is as powerful as VMware Workstation’s.

64-bit guest support

It is hard to believe but Virtual PC 2007 SP1 doesn’t support 64-bit guest operating systems. You can run it on a 64-bit host, though. VirtualBox supports 64-bit hosts and guests. You probably know that there is no 32-bit version of Windows Server 2008 R2. Thus, Virtual PC is no option if you want to try Microsoft’s latest server operating system. I ran Windows Server 2008 R2 on VirtualBox and it worked fine; just the virtual machine additions are not yet supported. This also applies for Windows 7. Basically, this means that there is no clipboard support (you can’t use copy and paste text between host and guest) and there is no seamless mouse integration (you have to press STRG to leave the VM with the mouse pointer). You might also recognize slower video output without the guest additions. I hope the next release will bring this feature.

Support for Linux, Mac OS X, FreeBSD, OpenBSD and Solaris as guest OS

Virtual PC supports only Windows as guest OS. There is an emulation for the PowerPC-based Mac OS X, but as far as I know you can’t run the x86 edition. You might be able to get Linux running on Virtual PC if you are a geek. But many report problems and it is not officially supported. VirtualBox on the other hand isn’t that choosy about the guest OS. If you like to look beyond the Windows horizon every now and then, then VirtualBox is certainly the better choice. Moreover, VirtualBox can be installed on Windows, Apple OS X, Linux, and Solaris.

Performance

I didn’t measure the performance difference between Virtual PC and VirtualBox myself. However, I have read several times that VirtualBox is faster. Tim Anderson compared the performance of VirtualBox 1.5.5 and Virtual PC using the PassMark suite and found that VirtualBox is about 50% faster than Virtual PC. The current edition of VirtualBox is 2.1.0. It is possible that the difference is even bigger now. Especially when you run multiple guests performance is an important factor even if you are only testing. (The Mars Box has a comprehensive performance comparison between VirtualBox and VMware Workstation.)

Remote Virtual Machines (RDP support)

If you have your virtual test environment on a remote server, then you will like the VirtualBox’s VRDP feature. VirtualBox has a built-in RDP server (VRDP) which allows you to connect to virtual machines with any RDP client. This is especially useful if your test environment uses private IPs and NAT because you can use the host’s IP for the RDP connection. To avoid conflicts with the RDP server of the host it is advisable to change the RDP port of the virtual machine. Each VM can have its own unique RDP port which allows you to connect to multiple VMs simultaneously. Note that the guest’s RDP server doesn’t have to be running. This should work even if the guest OS is Linux. I didn’t try this, though. Another cool VRDP feature is that you can access local USB devices within the virtual machine that runs on a remote server.

VHD and VMDK support

VirtualBox has its own disk format VDI (Virtual Disk Image), but it can open Microsoft’s VHD (Virtual Hard Disk) format and VMware’s VMDK (Virtual Machine Disk File) format. You don’t have to import or convert virtual disks to load a third party virtual machine. This can be useful, if you already have virtual machines that you want to continue using with VirtualBox. Furthermore, it is possible to evaluate Microsoft software through its pre-configured VHDs . At least, this is the theory. I tried to launch two VHDs with VirtualBox on a Vista x64 host and it failed to open with the error message invalid pre-header. Sun already knows about this bug and it should be fixed in the next version. I was able to open a VMDK file that I created with VMware Workstation 6.5 in VirtualBox, but older VMware virtual machines did not boot up. I suppose there are ways to get these VMs running too. However, you probably have to invest some time.

I didn’t discuss all the VirtualBox features that Virtual PC lacks (for example, multiple monitor support for the guest, or the ability to install VirtualBox on a GUI-less host), but it should be clear by now that VirtualBox is the more powerful virtualization solution.

Note that there are two editions of VirtualBox, an Open Source version and a commercial version. The commercial version is free of charge for personal and educational use. Commercial use for individuals within a company is also free if no more than one client connects to the host at a time.

The Open Source edition is released under the GNU General Public License (GPL) and lacks these features: RDP server, iSCSI support, Gigabit Ethernet Controller, and Serial ATA Controller.

The only feature I really miss in VirtualBox is the ability to create linked clones. It is the only reason that I stick with VMware Workstation. Linked clones are copies of a virtual machine which only contain the changes made to the guest. This reduces the storage space significantly if you work with many virtual machines. However, if the decision is between Virtual PC and VirtualBox, the better choice is obvious.

• FREE: vWorkspace Desktop Optimizer – Optimize VDI performance (0)
• SCVMM 2012 review – Part 5: Integrating with VMware and Citrix XenServer, Cluster patching (0)
• VMware Backups – Troubleshoot the Consolidate Helper-0 backup error (1)
• Installing a driver in an existing VMware vSphere 4.1 ESX/ESXi host (1)
• How to add VMware vSphere 4.1 ESX/ESXi hosts to Active Directory (1)

SolarWinds free VM Monitor is an ingenious desktop tool that continuously monitors a VMware ESX Server and its virtual machines, delivering the real-time monitoring of ESX Servers that you’ve been missing. With VM Monitor at your fingertips, you’ll be able to track virtual server health at-a-glance and ensure your mission-critical apps never fail you… after all, VM Monitor ensures you are visually alerted in real time to any issues in your virtual reality. SolarWinds free VM Monitor makes it easy to:

• Quickly check the health of your VMware ESX Server by monitoring CPU, memory utilization, number of virtual machines configured and running, and much more
• View detailed virtual machine health statistics including VM name, guest OS, and VM state, as well as processor, memory, and network usage
• Leverage best practice thresholds to begin monitoring virtualized servers right out-of-the-box
• Prevent performance degradation by watching threshold-specific indicators to visually alert you when problems occur

SolarWinds VM Monitor

• Poll: Are you currently using a monitoring solution? (11)
• SCOM 2012 review – Part 8: Dashboards (0)
• SCOM 2012 review – Part 7: Linux and JEE monitoring (4)
• Notifications and Custom Commands in Nagwin/Nrpe (0)
• SCOM 2012 review – Part 6: Application Performance Monitoring (APM) (1)

Sophisticated virtualization technology does not come for free. Yes, there are a couple of free solutions available. However, they have important downsides. The most prominent solution is probably VMware Server. You could run it on a Linux host without any license costs. But we all know why VMware offers this product for free. It is not just because of Microsoft’s Virtual Server. The main reason is that they want you to buy VMware ESX after you started to like virtualization technology. You will want to have more performance, more redundancy and many other features that VMware Server lacks. Of course, this is an absolutely legitimate strategy. However, for most organizations it will mean they will pay sooner or later for virtualization technology. These costs certainly also have to be taken into account when it comes to the overall costs of server virtualization.

Note that it is not different with Microsoft’s Hyper-V. I don’t just mean that you have to purchase a Windows Server 2008 license to use it. I guess it won’t take long before Hyper-V Server will come out, a bare metal hypervisor that doesn’t require a Windows license. Of course, Microsoft also wants to make money with virtualization technology. To benefit significantly from server virtualization, you need sophisticated management tools, especially if you want to compensate for the biggest disadvantage of server virtualization – the reduced redundancy. In other words, you have no other choice but to invest in these tools. Rest assured that, over time, they will become more powerful but also more expensive. These costs have to be considered too.

However, it is well known that the key factor of the total cost of ownership (TCO) is neither software nor hardware nor electricity. You won’t be surprised to hear that the main cost factor in any IT department is you, dear administrator! Everyone talks about server consolidation, but what about “administrator consolidation“? Can server virtualization be helpful here?

There is no doubt that virtualization technology adds a new layer of complexity to our IT infrastructure. More complexity usually requires additional IT professionals. At least this is true at the beginning when you introduce virtualization technology. Large organizations in particular have no other choice than to employ virtualization specialists if they plan to virtualize a large number of their servers. The administrators they already have will be needed to manage the virtual servers; the fact that you have fewer physical servers does not reduce the number of applications you have to maintain.

Server virtualization saves costs when it comes to the management of physical servers. Large companies might need less people to install the servers to their racks. However, I think these cost savings are more or less negligible because a server has to be replaced only once in five years and you do not need Einsteins to do this kind of work. On the other hand, the virtualization specialists certainly earn a little more and will be busier once the servers have been installed.

So, server virtualization doesn’t make sense at all? On the contrary, I do believe that in many cases you can benefit from virtualization technology. In my view, the real advantage of server virtualization is the new flexibility that it brings to server management. For example, the ability to move a virtual server easily to another host, to take snapshots or to duplicate complete servers in couple of seconds, are features that any administrator would like to have. Hence, once the IT staff has mastered the virtualization technology it will improve productivity in the IT department. Since server virtualization can also reduce downtime, it can help to increase productivity in other parts of an organization.

In conclusion, it is not server consolidation, but rather server flexibility that provides the real benefit of server virtualization. In most cases server virtualization will mean extra costs for an organization. However, since it also can increase productivity this extra costs are often justified. I think it is important for an IT manager to consider this because if at the end of the year your CEO wants to know why the promised cost reductions didn’t come true after you introduced server virtualization, you should be prepared to give a reasonable answer.

Articles in this series:

• Seven disadvantages of server virtualization
• Does server virtualization reduce costs? Part II – Power savings
• Does server virtualization reduce costs? Part I – Hardware expenses
• Does server virtualization reduce costs? Part III – Software and payroll costs

• FREE: vWorkspace Desktop Optimizer – Optimize VDI performance (0)
• Hyper-V upgrade – Conclusion (4)
• Hyper-V upgrade – The process (2)
• Why I am upgrading from Hyper-V 1.0 to 2.0 (0)
• SCVMM 2012 review – Part 6: Self-service empowerment, service deployment and conclusion (1)

I suppose a well-fed sumo wrestler consumes ten times as much food as a ballerina. However, ten ballerinas have a fair chance to floor a sumo wrestler. Power consumption is connected to the amount of work that has to be done. Thus, if a high-end server has to do the work of ten average servers, it obviously needs a lot more power than each of them does.

Of course, most supporters of the power savings claim are aware of this fact. Their point is that servers also consume much power when they are idle. Since a high-end server running ten virtual servers is seldom idle, it will use energy more efficiently. This argument is certainly valid if you assume that the ten average servers are oversized for their tasks and, therefore, often consuming energy without doing valuable work.

However, there are other factors to consider here. Much of the electrical power a server consumes is transferred into heat that has to be abducted. The problem is that heat abduction for an object with a small surface is more difficult than for a big object. This is the reason why the fans in computers are becoming bigger and bigger over the years. I remember quite well that my first computer didn’t even have a fan. The point here is that fans require energy too. The more CPU power that a computer of a certain size has the more energy you will need to get rid of the heat. Obviously, a high-end server has less volume than ten average servers do; this means that you need more energy for cooling this server than for multiple servers having a bigger surface.

Even though the high-end server is well equipped with fans, its CPUs, power supplies, and hard disks will always operate at a higher temperature than those in the ten average servers. This is where the second argument comes in: You will waste more energy for heat (thermal energy) if you run your system at a higher temperature. Imagine a sprinter who has to run one hundred meters in ten seconds. Even if he is well trained he will be sweating a lot. Now imagine ten average persons who have to walk ten meters in ten seconds. Together they also covered one hundred meters, but they won’t sweat. They won’t feel as exhausted as the sprinter will, even if you were to repeat the experiment ten times. However, our runner would most likely be dead afterwards.

I know this metaphor is a bit far-fetched, but I think you understand my point: you can’t always save energy by simply reducing the number of workers. Many factors have to be considered here. If you were to replace ten old servers with one new high-end server, you would probably not measure reduced power consumption afterwards. Perhaps five new average servers without virtualization technology would have been able to do the job as well? Would those five average workers have needed less energy than your sprinter?

If, and by how much, you can reduce in power costs with virtualization technology depends heavily on your environment. I doubt whether a general formula exists, that can calculate that for you. Personally, I do think that one can save power in some cases by virtualizing servers. However, it seems to me that the benefits are often exaggerated by vendors trying to sell high priced high-end servers or virtualization software.

I searched Google for a scientific study that would extend the analysis beyond the typical “idle time argument” but I was not able to find one. This made me even more suspicious. If you are aware of such a study from an independent scientific institution I would be very much interested.

When it comes to the costs of server virtualization, the power savings are outweighed by other factors anyway. This will be the topic of my next post in this series.

Articles in this series:

• Seven disadvantages of server virtualization
• Does server virtualization reduce costs? Part II – Power savings
• Does server virtualization reduce costs? Part I – Hardware expenses
• Does server virtualization reduce costs? Part III – Software and payroll costs

• FREE: vWorkspace Desktop Optimizer – Optimize VDI performance (0)
• Hyper-V upgrade – Conclusion (4)
• Hyper-V upgrade – The process (2)
• Why I am upgrading from Hyper-V 1.0 to 2.0 (0)
• SCVMM 2012 review – Part 6: Self-service empowerment, service deployment and conclusion (1)

The arguments supporting this claim are so obvious that most IT managers do not dare question them. Replacing ten physical servers with just one seems to be the best cost-saving measure one can think of – and since the Green IT hype began, even CEOs talk about power-saving in the data center. The calculation seems to be quite easy, too: ten horses require ten times as much hay as one horse. Every CEO can understand that. So does it really make sense to challenge the costs saving axiom of server virtualization? I think it does.

There are four different considerations to take into account when it comes to calculating the cost of server virtualization: hardware costs, power costs, software costs, and payroll costs. I will cover the first factor today, and the others in the next articles in this series.

It is a fact that the claim that ten servers cost less than one server is not always true. This is not surprising because the same applies to other objects such as cars: ten Volkswagens can be cheaper than one Ferrari. We have pretty much the same situation when it comes to server virtualization.

The price of a server is not proportional to its computational power. High-end servers are disproportionately more expensive than average servers are. There are many reasons for this. For example, a 4 GB RAM module costs more than two 2 GB RAM modules. Moreover, a server that can host ten virtual servers obviously needs a lot of RAM. The same applies to most of the other components of a server such as CPU power, storage, etc.

Another key factor is that server vendors produce more small servers than high-end servers, which drives up prices of the latter. This means that you cannot always save hardware costs if you replace ten servers with one server that is powerful enough to do the same job.

The reason why many IT shops experience cost savings when they move to server virtualization is that their previous physical servers were hopelessly oversized. It is certainly one of the advantages of server virtualization, that it is easier to fine-tune hardware utilization. However, the huge cost savings that people sometimes report are often because they did not care much about server utilization before.

In fact, it is not necessary to host every backend application on a single server. The argument that this might avoid conflicts between different server applications can be countered with the argument that server virtualization can cause problems too, since it adds a new complexity level. In addition, let us not forget that virtualization is always at the expense of performance and this increases the investments in required server hardware.

Whether, and by how much, hardware costs can be reduced by means of server virtualization depends heavily on the server infrastructure of your organization. If you have already optimized hardware utilization by other means, then server virtualization will not be much helpful in reducing hardware costs. One thing is for sure: I would not put my faith in the cost calculation tools of server virtualization vendors. In my view, it is not possible to calculate such costs using a general formula.

There is another thing you should consider. Why do hardware vendors such as Intel or IBM promote server virtualization? Why does this technology not scare them to death? I mean, if everyone can save so much in hardware costs with server virtualization, server vendors would have a serious business problem. I somehow think that vendors just like the idea of selling more high-priced high-end servers. In fact, you can earn more by selling just one Ferrari, even if the ten Volkswagens have the same price.

In addition, even if you can reduce costs by replacing ten servers with one high-end server, you have to take into account that you also reduce redundancy this way. If your host goes down because of a hardware malfunction, everything stands still. Yes, you can add a second or a third server and work with cluster technology, but this will again raise hardware costs and adds yet another layer of complexity. It will be quite difficult to save on hardware costs if you replace ten average servers with two or three high-end servers.

Articles in this series:

• Seven disadvantages of server virtualization
• Does server virtualization reduce costs? Part II – Power savings
• Does server virtualization reduce costs? Part I – Hardware expenses
• Does server virtualization reduce costs? Part III – Software and payroll costs

• FREE: vWorkspace Desktop Optimizer – Optimize VDI performance (0)
• Hyper-V upgrade – Conclusion (4)
• Hyper-V upgrade – The process (2)
• Why I am upgrading from Hyper-V 1.0 to 2.0 (0)
• SCVMM 2012 review – Part 6: Self-service empowerment, service deployment and conclusion (1)

I will reproduce the heading of DABCC article and sometimes a quote from Douglas Brown’s arguments, and add my comments afterwards.

1. Hyper-V is marketed as free but really isn’t.

Yeah it’s $28 bucks but that’s on top of a Windows 2008 License paid in full.

This is the first time I’ve heard that Hyper-V is marketed as free. At the moment, Hyper-V is just a feature of Windows Server 2008, like IIS7. Nobody ever said that IIS7 is free, so why should Hyper-V be free?

Anyway, the main mistake here is that Brown confuses two different products. According to this Microsoft press release, it is not Hyper-V, but Hyper-V Server that will cost $28. Hyper-V is a part of Windows Server 2008, and Hyper-V Server will be a hypervisor-based virtualization product which will be delivered by hardware vendors. As far as I know, it is not available yet.

I think what Brown wants to say is that ESX is cheaper than Hyper-V (not Hyper-V Server) if you add the licensing costs for Server 2008. However, the real price depends on many factors. It depends on the number of servers you want to virtualize and on the Windows server edition you run on the host system. For example, if you buy the Enterprise edition, you get 4 Windows Server licenses for the VMs and with Datacenter edition, you don’t pay anything for the Windows Sever guests. It also depends on the VM management product you will use. So I think there is no general answer to the question of which product is cheaper. It depends on your environment. If you intend to virtualize only Linux servers, you probably will pay less with ESX.

2. Hyper-V is not actually bare metal.

If Hyper-V isn’t bare metal, then ESX isn’t either. The only difference between ESX and Hyper-V here is that VMware uses a modified version of Red Hat Linux in the root partition and Microsoft uses Windows for this purpose. Of course, the advantage of Hyper-V is that it runs on every PC that supports hardware virtualization because there are more device drivers available for Windows. This is certainly an advantage of Hyper-V.

3. MS target market is low margin with little to gain because SMBs aren’t ready.

I doubt that Microsoft only targets SMBs. It is true that VMware ESX is technically advanced, but it is certainly wrong to put Hyper-V on the same level as VMware Server. VMware Server is comparable to Virtual Server. There is no doubt that Hyper-V offers better performance than VMware Server and also Virtual Server. Thanks to paravirtualization, it might even be faster than ESX in some environments.

However, my point is that when it comes to virtualization, Microsoft’s main product is not Hyper-V, but Virtual Machine Manager 2008. It was quite a smart move to support ESX in VMM 2008. Most virtualization experts agree that the hypervisor will only play a minor role in the upcoming battle between VMware and Microsoft. What counts are the management products. VMware is still leading here though. But we all know that Microsoft is not too bad at developing system management products.

4. Hyper-V ties the hypervisor back to the OS.

I already said it above. There is no real conceptual difference here between ESX and Hyper-V. If you worry about the overhead of a bloated Server 2008, you can run Hyper-V on Server Core. However, I suppose that Brown is referring to the fact that hardware vendors integrated the ESX hypervisor in their products, so he writes:

MS will have to release a true bare metal product to compete with VMware and they need to do it soon. I highly doubt they will though as Windows is integral to Hyper-V’s ability to do half of the things ESX does.

I wonder what reasons he has for these doubts. Didn’t Microsoft announce that they are already working on a “bare-metal” edition of Hyper-V in this press release?

5. Virtual Machine Density is a fraction of what is possible.

In this argument, he refers to the memory resource management features memory overcommitment feature of ESX. As far as I understand it, the main idea here is to virtually assign more memory to your VMs than is actually physically available. It is certainly a matter of fact that the amount of memory a server requires varies over time. Thus, with this technology you can run more VMs on a host than you can without it.

I must admit I have no experience with this feature, but I doubt that I would like to use it in a productive environment. The problem with any virtualization technology is that you run software in an environment for which it wasn’t developed. This can cause unforeseen problems. The farther you move away from a standard environment, the riskier it will be. And this technology sounds very freaky to me. I wouldn’t even configure virtual disks to grow dynamically in a productive environment. The main issue certainly is performance here. However, I also feel much more comfortable if VMs can rely on the resources that were assigned to them.

Anyway, memory resource management is only one feature of ESX that Hyper-V doesn’t have. There is no doubt that VMware is still ahead of Microsoft. The main point of my article is just that the five reasons given by Brown are not really the best ones. I do believe that there are good arguments for preferring ESX over Hyper-V.

I also do not want to rule out that some of my assumptions are incorrect. As I said before, one of the reasons why I wrote this post was because I am puzzled by the DABBC article. Please, let me know if you have any other information.

• FREE: vWorkspace Desktop Optimizer – Optimize VDI performance (0)
• Hyper-V upgrade – Conclusion (4)
• Hyper-V upgrade – The process (2)
• Why I am upgrading from Hyper-V 1.0 to 2.0 (0)
• SCVMM 2012 review – Part 6: Self-service empowerment, service deployment and conclusion (1)

I will discuss all seven downsides from my own perspective and share some of the experiences we have had with server virtualization.

1. Magnified physical failures

Imagine you have ten important servers running on one physical host and its RAID controller runs amok, wiping out all of your hard disks. Don’t say that this is not very likely, as we have already had two or three incidents from malfunctioning RAID controllers from well-known brands.

There are several ways to compensate for this downside. One is clustering, which certainly entails extra efforts. Another answer is to backup the virtual machines with a CDP (Continuous Data Protection) solution. If your physical server goes down, it is possible to restore all VMs quickly to another host. This solution implies that you have enough capacity left on another host. Thus, if your virtual infrastructure is well planned, physical failures may be less problematic. However, this means that you have to invest in redundant hardware, which more or less eliminates one of the alleged advantages of server virtualization.

2. Degraded performance

There is no doubt that virtualization requires extra hardware resources. The problem is that it is almost impossible to estimate in advance how many extra resources will be needed. I know that there are capacity planning guides and tools but from my experience every piece of software behaves differently in a virtualized environment. We have applications that are quite modest as long as they run on a physical server, but when they were virtualzed their resource requirement multiplied.

You can’t do much if you have such applications. In our case, we had no choice but leave them on physical servers. Hence, the only solution to this problem is to thoroughly test each application with the virtualization solution of your choice.

3. New skills

It sounds so easy – install a virtualization solution and then just deploy your servers as you are used to. Not really! Many things are different in a virtual environment. I will give you just one example. When we installed our first server virtualization solution, I instructed our administrators to test some of their servers in the virtual environment. After a week or so, an administrator told me that he could not test his server because there was no more RAM available on the host. I was quite surprised, as this server has enough capacity for 10 VMs.

When I logged on, only 3 VMs were actually running. What happened? Some of his fellow administrators had assigned the same amount of RAM to the virtual servers as their physical servers had required. It took me quite some time to convince them to change their working habits. When you buy a new physical server, it is common practice to equip this server with as much memory as your budget allows. This makes sense, as it takes time to order new memory modules and add them to the server. Even if you do not require it now, you will most likely require more RAM very soon.

Of course, this situation is different in a virtual environment. I assign blame to myself, as we should have discussed things in advance. I should have told the administrators that they first need to figure out how much RAM their servers really need using a performance monitoring tool. If their server requires more RAM later, it is not a big deal to assign more. I chose this simple example because it demonstrates that you have to do some rethinking when you work in a virtual environment. The fact that several administrators share one physical server causes problems that didn’t previously exist. Of course, it is also necessary to acquire many new technical skills.

4. Complex root cause analysis

Virtualizing a server certainly implies big changes to the whole system. A new layer of complexity is added and can cause new problems. However, the main difficulty is that if something doesn’t work as it is supposed to, it can require considerable extra efforts to find the cause of the problem. I have another example for this downside of server virtualization.

We installed a SUSE Linux server under Virtual Server 2005. Everything worked fine at first. But, then the admin reported that his SSH sessions often got disconnected. We had another Linux machine running on the same host which didn’t show this behavior, so we thought it must be a configuration problem on the Linux system. However, this skilled Linux administrator wasn’t able to find the problem’s cause. I then had the idea to move this virtual machine to another Virtual Server host – and the problem was gone. So did Virtual Server or Linux cause the problem? Well, I can’t tell you. We never figured it out.

5. New management tools

Virtualization also has advantages, such as easier migration, cloning or snapshots. However, you can only take advantage of these new capabilities if you have the proper tools. Often, the tools that come with a virtualization solution are not enough, only supporting basic management tasks. This means that you need additional utilities, which cost both money and time. I am not only talking about such tools as VMware Virtual Center or Microsoft Virtual Machine Manager (VMM).

Another important field is backup, or more precisely, disaster recovery. Of course, you can use your current backup software to secure your virtualized servers. However, one of the advantages of server virtualization is that disaster recovery becomes much easier and faster provided you have a backup solution that is able to perform live backups of the virtual machines and not just of the virtualized servers running in these VMs.

The problem lies in that there are no real standards when it comes to virtual server management. But, there are standards for server management in general. For example, there are many backup tools that allow you to secure your Windows, UNIX and Mac machines, but it is difficult to find a disaster recovery solution that supports all the various virtualization solutions out there. All in all, this means that your zoo of management tools will grow, meaning more work for you.

6. Virtual machine sprawl

Even though virtual server management can get quite complex, installing a new virtual machine is a piece of cake. You need a new server? Just clone your master image to a new VM and you are done within a few seconds. The problem is that the number of servers might grow faster than the number of admins who are supposed to manage them. It is good that even virtual servers have physical limits. As soon as you reach the limit of your virtual capacity, the virtual machine sprawl will naturally stop.

The number of servers in my department has grown significantly since we started working with server virtualization. As a matter of fact, quite a few of them exist only because it is so easy to create them in a virtual environment. Thus, you have to be very careful that you don’t waste the resources of virtual server hosts with unneeded virtual machines.

7. Virtual habits

I am not sure if I understand this argument in the Networkworld article:

Once IT organizations start to use virtualization, they can’t stop themselves, Coyle said.

Coyle is the Gartner analyst who is the source of the insights in the Networkworld article. He makes it sound like virtualization is a kind of addictive drug. Perhaps he meant that organizations that discovered the values of virtualization are prone to introducing virtualization technology in areas where it is better they stay physical. I also see this danger, and it is difficult to give advice on this subject. Sure, there are some general rules, such as don’t virtualize servers that have unpredictable resource requirements. However, I think that virtualization often causes problems in unforeseeable situations. Coyle gives the only possible advice here: “test, test, test.”

What are your experiences with server virtualization? Do you think that the downsides outweigh the benefits?

Articles in this series:

• Seven disadvantages of server virtualization
• Does server virtualization reduce costs? Part II – Power savings
• Does server virtualization reduce costs? Part I – Hardware expenses
• Does server virtualization reduce costs? Part III – Software and payroll costs

• FREE: vWorkspace Desktop Optimizer – Optimize VDI performance (0)
• Hyper-V upgrade – Conclusion (4)
• Hyper-V upgrade – The process (2)
• Why I am upgrading from Hyper-V 1.0 to 2.0 (0)
• SCVMM 2012 review – Part 6: Self-service empowerment, service deployment and conclusion (1)

I only played a little with Hyper-V, but I am already looking forward for the final to be released. At the moment we have two VMware Server 1.0 hosts and one Virtual Server 2005 machine. Both solutions work fine, but only for server applications that don’t need much performance. We tried a couple of more demanding applications, but those tests all failed. It is interesting to note that VMware Server was always slower than Virtual Server when Linux was the guest OS.

We have been considering buying VMware ESX, but in my view, it is too expensive. The main advantage of virtualization is to save costs, but in our environment it would get more expensive with VMware ESX. Even though, VMware certainly has the better product, I see hard times are coming for them as soon as Hyper-V is released. But who knows, maybe they will reduce their prices. VMware GSX once was quite expensive, too. I guess we will soon know what the lowest possible price for VMware ESX is.

We are planning to test Hyper-V soon to see if its performance is really better than with Virtual Server and VMware Server. I will then report about it here. Stay tuned!

• FREE: vWorkspace Desktop Optimizer – Optimize VDI performance (0)
• Hyper-V upgrade – Conclusion (4)
• Hyper-V upgrade – The process (2)
• Why I am upgrading from Hyper-V 1.0 to 2.0 (0)
• SCVMM 2012 review – Part 6: Self-service empowerment, service deployment and conclusion (1)

I added the page views behind the title of the article. The numbers are from Google Analytics. Note that they do not represent the absolute page views in 2007 since I started using Google Analytics only at the end of March.

1. How to disable Vista’s desktop search indexing (Windows Search) 49299
2. Expanding a virtual VMware disk 42539
3. Install Windows Server 2003 Adminpak (Administration Tools Pack) on Vista 34035
4. Adminpak for Windows Vista 33013
5. Vista x64 vs. Vista x86 – 32 bit or 64 bit Vista edition? 29714
6. ioDrive: 640 GB flash card almost at the speed of DRAM – The end of hard drives? 27027
7. Windows Vista 32-bit versus Vista 64-bit 21264
8. Resize a Virtual Disk with VMware Converter 15763
9. Vista compatibility update for the Adminpak 12174
10. Three ways to reset a Windows Vista admin password 11378

I must admit that I was a bit surprised that the most read article was about Vista’s desktop search indexing. It appears to be one of the new Vista features that were a flop.

However, the most popular topic was another one. Three articles about the Adminpak problem made it in the top ten. I still don’t understand why Microsoft neglected this issue. Aren’t the admins the ones who have to be persuaded first to move to a new operating system version?

Also interesting is the number of people that have had problems with expanding VMware disks. When I first came across this issue I couldn’t believe that VMware didn’t offer a simpler solution.

Not so surprising is that many were unsure if they should install Vista x86 or Vista x64. I suppose that the 64-bit edition will soon gain more popularity. At the moment 3GB are enough for most users. However, I think that in one year many power users will already thirst after more memory.

So what are the prospects for 2008? I guess the number one topic will be Windows Server 2008. I already posted a lot about it and I am sure there will be more to blog about it as soon as its final becomes available. By the way, my German speaking readers (I know there are many) might be interested in an article about Windows Server 2008 I am writing for the German magazine Computerwoche. I am constantly extending it since it is a wiki entry.

Another thing I will concentrate on in 2008 is finding new sponsors for 4sysops. You might have realized that I removed Adsense some weeks ago. It simply didn’t perform well recently. Blogging is certainly fun, but it is even more fun if you can earn a little with it. So I also have to say thanks to my new sponsors Special Operations Software and NETIKUS.NET.

Ok then, enough blogging for this year. Happy new year!

• Microsoft Exam 70-640 – DNS Zones – Overview (2)
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