VMware Site Survey is a very useful utiltiy from VMware that allows you to test whether or not your VMwar environment is ready to use new VMware features such as Fault Tolerance. You can download the utiltiy from VMware website. It runs from your desktop and connects to vCenter. At the end you are presented with an HTML report which explains the results and why certain component is not compatible with new feature(s). It also provide links to HCL for certain hardware.