Technical Reasons Not To Upgrade to vSphere Immediately: Product Compatibility
June 18th, 2009 | 
Author: In my opinion, there are only a handful of reasons not to implement vSphere 4 immediately and all of them are temporary, techincal limitations. My list of reasons:
- 64 bit hardware (or virtualization assist CPUs) requirement
-
Already Implemented the following VMware products
- vCenter Stage Manager
- vCenter Lab Manager
- vCenter Site Recovery Manager
- vCenter Lifecycle Manager
- VMware View (Manager and Composer)
These are temporary limitations because VMware has already announced compatibility for all of their solutions with vSphere will be available in the second half of 2009. Of course, buying 64 bit hardware with modern CPUs could make you wait a little longer depending on your ’09 budget.
VMware has a Software Compatibility Matrix that helps identify supported combinations of all their virtualization products. Here’s a screen shot.
Click for a larger image or get a copy of the .pdf at http://partnerweb.vmware.com/comp_guide/docs/vSphere_Comp_Matrix.pdf
Interestingly enough, a Virtualization Pro Blog post seems to confirm a majority of VMware users seem to be waiting at least 6 months to upgrade to vSphere. Upgrading production servers to vSphere: When and why analyzes the results of several polls conducted by the author, Eric Siebert.
Read the rest of the post for further analysis from Siebert and the results of additional, related poll topics such as the primary reasons for waiting to upgrade. Although the majority of responses do not indicate a decision to wait because of the technical limitations I indicate here, the preference to allow some time before implementation allows for a fully supported data center on vSphere 4 in the near future.
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Rich,
Another technical reason that I have been running into is Ranger Pro.
Clients that have become very heavily invested in using VizionCore's RangerPro for their virtual backup strategy are now stuck in the lurch with RangerDPP still only in BETA and the old RangerPro not compatible with vSphere.
This has also made them begin to start looking at Veeam as an alternative which already has vSphere support.
CARLO.
I think the biggest technical reason of all is ESX 4 has basically a rewritten kernel,
it's a major change, and many enterprises will want to thoroughly test it under
conditions similar to the production load, to ensure it's actually stable, and won't
present unknown issues.
Of course there are non-technical reasons also, like the VMware admins aren't familiar with or trained on how to manage the new version yet, people need to adapt to and understand the differences, some organizations will want their admins trained on it before making a plan to move their production servers to the new version.
Carlo, Dracolith,
Thanks for adding a few other, equally important reasons.
New technical reason: In ESXi, free version you can hot-add virtual disks and increase their size no license requirement.
In vSphere it doesn't work. You need an advanced license.
New technical reason: In ESX3i, free version, foundation, and standard you can hot-add virtual disks and increase their size no license requirement.
In vSphere ESXi4 it doesn't work. You need an advanced license for all hot add operations, even just adding a VMDK.
Tried it in the free version, verified it doesn't work. The VMware comparison chart for vSphere features lists it as an “Advanced” feature.