Understanding the Impacts of Mixed-Version VMware vCenter Server Deployments
Adam Eckerle wrote an interesting blog post a few days ago. Find his blog post here – or simply scroll down for more information.
Thanks Adam for this detailed information.
There are a few questions that come up quite often regarding vCenter Server upgrades and mixed-versions that we would like to address. In this blog post we will discuss and attempt to clarify the guidance in the vSphere Documentation for Upgrade or Migration Order and Mixed-Version Transitional Behavior for Multiple vCenter Server Instance Deployments. This doc breaks down what happens during the vCenter Server upgrade process and describes the impacts of having components – vCenter Server and Platform Services Controller (PSC), running at different versions during the upgrade window. For example, once you get some vCenter Server instances upgraded, say to 6.5 Update 1, you won’t be able to manage those upgraded instances from any 5.5 instances. While most of the functionality limitations manifest themselves when upgrading from 5.5 to 6.x, there could also be some quirks in environments running a mix of 6.0 and 6.5. There are a couple of additional questions that seem to arise from this doc so let’s see if we can address them.
The Upgrade ProcessI’m not going to go through the entire process here, but it is important to understand the basics of how a vCenter Server upgrade works. Remember that there are two components to vCenter Server – the Platform Services Controller (PSC) which runs the vSphere (SSO) Domain and vCenter Server itself. For a vCenter Server upgrade, the vSphere Domain and all PSCs within it, must be upgraded first. Once that is complete, then the vCenter Servers can be upgraded. Obviously, if you have a standalone vCenter Server with an embedded PSC, this is a much simpler proposition. But, for those requiring external PSCs because of other requirements such as Enhanced Linked Mode, just remember the PSCs need to be upgraded first.
Read the entire article here, Understanding the Impacts of Mixed-Version vCenter Server Deployments
Via the fine folks at opvizor.