You can use the vSphere Web Client to access the ESXi license key.

Procedure

  1. From the vSphere Web Client, connect to the vCenter Server.
  2. Select the host in the inventory.
  3. Select the Manage tab.
  4. Select Settings.
  5. Select System.
  6. Select Licensing.

Results

The license key appears in the form XXXXX-XXXXX-XXXXX-XXXXX-XXXXX.