VMotion stops working with a "License server is not configured" error after upgrading to vSphere 4
Symptoms
Unable to VMotion after upgrading from VirtualCenter 2.5 to vCenter 4.0 and ESX hosts are 3.5.
Licensing information not correctly displayed after upgrading from VirtualCenter 2.5 to vCenter 4.0.
Licensed Features summary for ESX shows VMotion as Not Used.
Licensed Features summary for ESX also shows DRS, HA and vCenter agent as Unlicensed Use.
VMotion fails.
Unable to re-enable VMotion after disabling. Attempts to disable and re-enable VMotion on the VMotion interface results in the error:
The license server is not configured to perform the operation
Attempts to reconnect an ESX host in vCenter after becoming disconnected produces the error:
VI3 hosts cannot be added if vCenter is licensed but License Server is not configured. Configure License Server and try again.
Resolution
There are 2 parts to this resolution.
If you have incorrect Licensed Features information displayed:
Verify the VMware Infrastructure 3 license server is operating.
In vCenter, go to Administration > vCenter Server Settings > Licensing.
Verify that the License Server field is populated. If it is not, enter the FQDN of the server running the VMware Infrastructure 3 license server (usually the vCenter Server that has been upgraded to vSphere).
Verify that the correct Licensed Features information now displays for HA, DRS, and vCenter agents.
If you are unable to VMotion you must disable and re-enable VMotion on the network interface.
To disable and re-enable VMotion on the network interface:
Log in to vCenter Server using the vSphere Client and select the host in the inventory.
On the Configuration tab, click Networking.
Click Virtual Switch to display the virtual switches for the host.
Locate the virtual switch that has a VMkernel port group configured for VMotion, and click the Properties link.
On the Ports tab, choose the port group that is configured for VMotion and click Edit.
On the General tab, deselect Enabled for VMotion.
Click OK to close the port group Properties dialog, and click Close to close the vSwitch Properties dialog.
Perform steps 4 through 7 again, this time selecting Enabled for VMotion.