Re: Upgrade existing vCenter 5.0 to 5.1 with SSO

I actually just did this if you want to reference my blog, but I split services out. You will want to unlink your vcenters first.  I didn't document the Multisite mode for SSO, but you will most likely need this for your setup and linked mode.

http://nutzandbolts.wordpress.com/2013/05/28/vcenter-5-0-to-5-1-u1-upgrade-while-splitting-out-services-part-1-sso-install/