You can assign a license key to an ESXi from the Licensing page in the vSphere Client.

If the vSphere Client is connected directly to the host, on the host Configuration tab click Licensed Features > Edit to change the license key.

Verify that you have the Global.Licenses privilege.

Ensure that the vSphere Client is connected to the vCenter Server system.

1

In the vSphere Client, select Home > Administration > Licensing.

2

In the Management tab, right-click a host and select Change license key.

3

Assign a license key.

Select Assign an existing license key to this host and select a license key from the Product list.

Select Assign a new license key to this host, click Enter Key, and specify a license key and an optional label for the license key.

4

Click OK.