Recommendations on Virtual Hardware Upgrade?

[aaronwsmith]

Hey everyone,

Working through the vSphere 5.1 upgrade and trying to decide whether or not to upgrade the virtual hardware for the VMs to the latest version.  The following KB states that VMware recommends upgrading to virtual hardware 8 or 9 when running vSphere 5.x, but doesn't clarify why:

http://kb.vmware.com/kb/1010675

This KB is the only place I've found (so far) where VMware is making this kind of recommendation about what virtual hardware version you should be running.

In general, I understand virtual hardware upgrades enable additional capabilities within the VM, such as the ability to add more RAM and vCPUs or access to new virtual hardware components.  So I could understand if the recommendation is being made simply to stay current.

But knowing that vSphere 5.1 supports virtual hardware versions 4 and 7 - 9 (most of our VMs are on v7) if we're not in need of the added capabilities that come with version 8 or 9, is it worth the effort vs. letting those VMs eventually retire through standard lifecycles or only upgrading their virtual hardware if/when they do need those additional capabilities?  We plan to update VM templates so new VMs going forward get the latest version, but I'm struggling to understand the rational behind the recommendation for existing VMs that working fine.

Any insight into this would be very helpful.  Thanks in advance!

[a_nut_in]

Hey Aaron,

This blog will help you with the additional features that virtual hardware 9 brings

http://www.vladan.fr/vmware-vsphere-5-1-virtual-hardware-version-9/

But since most of the features are enhancements and virtual hardware is also backward compatible,  best if you could weigh the additional featuresets and check if they really are relevant. If not, keep the existing hardware. The benefit would be easy roll back to lower versions of vsphere should anything go wrong in the upgrade process requiring a roll back

Regards

a

[aaronwsmith]

Thanks for the info!

I know VMware also originally promised the "no reboots" feature of VMware Tools with 5.1 + VM HW v9, but then clarified what those claims meant, which caused us to reevaluate the decision to upgrade the virtrual hardware for existing VMs:

http://blogs.vmware.com/vsphere/2013/02/clarification-on-zero-down-time-vmware-tools-uprade-in-vsphe...

http://blogs.vmware.com/vsphere/2013/02/is-a-vmware-tools-upgrade-required-when-upgrading-vsphere.ht...

http://kb.vmware.com/kb/2015163

We're considering establishing virtual hardware baselines, e.g:

Server 2003 - 2008 R2: v7

Server 2012: v9

Still looking at upgrading Tools utilizing the auto-upgrade on reboot functionality, since we can control tool upgrades in ESXi 5.1 via Image Builder/Update Manager.

Anyone know if any virtual hardware versions are created to address issues/security vulnerabilities in past versions?  Or have the virtual hardware upgrades always been just about enabling new features/capabilities within the VM?

[vmroyale]

Anyone know if any virtual hardware versions are created to address  issues/security vulnerabilities in past versions?  Or have the virtual  hardware upgrades always been just about enabling new  features/capabilities within the VM?

I've never heard of any vulernabilities being addressed by the virtual hardware versions, and think that they are provided to enable new features/capabilities.

[aaronwsmith]

Thanks for the feedback, very helpful!