VMware have not shouted about this one as much as they should have, given the potential gravity of the situation. If you use linked mode to connect multiple sites and have SRM 18.104.22.168 installed, then you will not be able to run an SRM recovery when you have the sites disconnected. As in, when you are experiencing a disaster which you want to recover from as quickly and painlessly as possible, as in, precisely what you purchased SRM for in the first place, you’re out of luck.
I recently saw a problem where a vCenter linked mode configuration appears to have failed half way through. It’s highly unusual in that from the C# Client when certain users log in to certain vCenters, they can see the newly added vCenter visible in linked mode as if everything was perfect. Other C# client users, anyone logging in to other vCenters or anyone using the web client does not see this intended end state.
More messing around in my lab and it was time to upgrade SRM from 5.5 to 5.8, including an update of the vCenter itself to 5.5 u2d as well as the IBM SVC SRA as precursors to the SRM upgrade itself. Upgrading vCenter is pretty simple as long as you run a custom installation and step through the components one at a time, SSO first through to vCenter 4th and last.
At this point, I am not going to go in to detail about the installation of SRM 5.x, as there are already lots of good blog posts / series out there about this. SRM 6.x though, fair game! However, I wanted to lay out some of the changes that should be made after an installation of your SRM environment before you start your testing, to give you the best chance of success as possible.