When I go to add the new license key, I receive the following error message:
Cannot complete the license assignment operation. The license on vCenter Server xxx.domain.com cannot be changed to vCenter Server 4 Standard. The vCenter Server with vCenter Server 4 Standard license needs access to a license server before it can manage hosts in the inventory. Update the configuration of the vCenter Server to include the license server.
If I drill down into the vCenter Server Settings and specify the name of the current license server and click ok I get this error message:
License not available to perform the operation. The license server at
firstname.lastname@example.org for vCenter Server xxx.domain.com does not include
vCenter agent for ESX Server. Upgrade the licenses on the license
This server was running vCenter 3.5U4 prior to the 4.0 upgrade. I have ports 27000 and 27010 open on the firewall as well as several others which the 4.0 install opened during installation. In the past, I would go to my account and download the license file, copy it to the license server, and then point the License Server tool to the new license file. However, that isn't how 4.0 works. The self-support documents do not seem to address upgrade scenarios and have extremely generic content. Google isn't any help either.
Some advice for upgrading to vCenter 4.0 from a v3.5 (or technically speaking 2.5.0U4) product:
1) If you have to use the same server, you should install VMware-licenserver.exe on another server. First copy your license.lic file to the new server. Next use the installer (which is located in the \vpx folder of the VIMSetup-2.5.0U4 iso). Make sure that server is32-bit windows. Don't forget to copy your license file to the new server.
2) In the VI3 manager, make sure you point your ESX hosts to the new license source (Configuration ->Software -> Licensed Features -> License Soruce)
3) Once all of your hosts are pointed to the new license server, uninstall the old license server.
4) Reboot & upgrade to vCenter 4.0. Make sure to have your 4.0 license key ready.
5) Once Installed, go to Administartion-> vCenter Server Settings -> Licensing, make sure you enter the hostname for the ESX 3.5 License Server -> OK
You should be good to go now. This guide is as useful if you're installing vCenter 4 onto a new server. If you're going that route, I'd recommend uninstalling VIM 2.5 prior to 4.0, especially if you're using a SQL database- you don't want two copies of VIM/vCenter writing to the database at the same time. This way you can leave the license server service installed on the old server while you migrate everything over to 4.0.
I installed the License server from vCenter 2.5.0 Update 5 on our development vCenter 4.0.0 management server, added a valid license file, and the License view within vCenter 4.0.0 showed the VI3 licenses. Our development ESX 3.x hosts were then able to pick up the appropriate licensed features. I would think that License Server from any recent vCenter should work.