Matrix to Determine VMotion Compatibility by Processor
There are several whitepapers, posts and articles already available to help you determine what processor models are compatible for VMotion between ESX hosts. I will provide some of those links at the end of this post. However, I stumbled across a new matrix published by Dell that, in my opinion, offers the easiest reference by processor model for preventing VMotion boundaries. Dell’s paper titled VMware VMotion and 64-bit VM Compatibility Matrix for VMware Infrastructure 3 and Dell PowerEdge Systems contains a VMotion and 32/64-Bit VM Compatibility Across Processor Models matrix that is easy to decipher. Of course, the .pdf provides a compatibility matrix by Dell server model number too.
Download the full paper at the link above, but the following image shows the CPU compatibility matrix for quick reference. Click on the image for a larger version.


