Upgrading to VMware vSphere 4? Check the HCL!

If you are upgrading your VMware VI3 compute complexes to VMware vSphere 4, you will need to confirm that all your hardware is certified for the release you are upgrading to.  Most hardware manufacturers will only do the certification work while a system is considered a current product.  This can be as short as two years. 

After a server, blade or storage array is no longer availible for sale, you may be STUCK on whatever ESX rev you are currently running.  This is a big problem for vManagers who want to use new features only availible for vSphere 4.   Even worse, VMware Update Manager makes it dangerously simple to upgrade your entire cluster to vSphere 4 with a few mouse clicks.  Regardless if your hardware is still certified.

• Keeping compute and storage hardware on a life cycle plan is critical, and keep that plan aligned as best as possible with the software.  
• Talk to your vendors, demand a policy on VMware HCL certification. 
• Understand your hardware vendor's product lifecycle
• Check the HCL: VMware's Live Hardware Compatibility Guide