Hyper- V Dynamic Expanding or Fixed Size VHD?


Hi, today I’d like to write about Hyper-V and Virtual Disks.

As you know Windows Server 2008 R2’s been released with bunch of enhancements in Hyper-V. One of the improvements is performance increase with Dynamic Expanding virtual hard disks (VHD).

Previously on Windows Server 2008 we didn’t recommend using dynamic expanding VHDs in production as its performance wasn’t quite comparable with fixed size VHDs. 

Now that Hyper-V product group has done such an awesome job of making dynamic VHDs par to fixed size VHDs, we get this question of whether these dynamic VHDs can be used in production or not?

Both virtual disk types are now supported in production. You may use either virtual hard disks based on your environment.

If you are trying to save space you need to use Dynamic Expanding virtual disks (VHD).

You can always expand the maximum size of Dynamic and Fixed VHDs (Using Edit Disk option in Hyper-V management Console or PowerShell script) if you need to.

The only important note here is to be careful about not oversubscribing the LUNs. This must be monitored closely if dynamic VHDs are being expanded frequently. 

What’s New in Windows Server 2008 R2 Hyper-V?


Also, please take time to review the following whitepaper;

Microsoft Hyper-V vs. VMware ESX & vSphere Operations & Management Cost Analysis White paper


So long!