We're upgrading from vCenter 4.1 to 5.5. The method that works best for us is to install vCenter 5.5 on a new server with a new database and then move our hosts from the 4.1 server to the 5.5 server one by one. We've already secured our license upgrade.
The next step is going to be to upgrade the vCenter license from the portal, and this is where we're stuck. VMware's been clear that we cannot continue to use the 4.1 license once we upgrade, but the 4.1 server will not be taken down for several days while we migrate the hosts to the new 5.5 server. Further, we cannot download 5.5 without performing the license upgrade. What is the appropriate course of action for us? Can we safely upgrade the license, apply it to the 4.1 server (while it is running 4.1) temporarily, then remove it from the 4.1 server and apply it to the 5.5 server once it is ready?
Please help, this hasn't been terribly clear in the documentation...