The first part of any hypervisor upgrade is to ensure that your existing hardware is supported. Part of that determination is what firmware levels are supported for your compute devices as well as necessary firmware for networking, fibre, blade chassis, etc.
vSphere upgrade saga: Upgrading HPSIM
Edward L. Haletky, aka Texiwill, is an author, analyst, developer, technologist, and business owner. Edward owns AstroArch Consulting, Inc., providing virtualization, security, network consulting and development and TVP Strategy where he is also an Analyst. Edward is the Moderator and Host of the Virtualization Security Podcast as well as a guru and moderator for the VMware Communities Forums, providing answers to security and configuration questions. Edward is working on new books on Virtualization.