Adding ESXi host to vCenter failed with error "Cannot complete the license assignment operation"

Products

• VMware vCenter Server

Issue/Introduction

Attempting to add\connect a host to the vCenter Server fails with the error after reaching to 90%:

Cannot complete the license assignment operation. Can not assign a license to "Host" <host_name>. Make sure the License Service is available.

Environment

VMware vCenter Server
VMware vSphere ESXi

Cause

This issue occurs when the vCenter has VMDir in read-only mode.

Resolution

Please perform the below steps to change the vmdir to NORMAL state:

Note: Ensure to take a backup of vCenter Server before proceeding.

1. Log in to the vCenter Server with SSH access.
2. Type shell and press Enter
3. Execute command:
   /usr/lib/vmware-vmdir/bin/vdcadmintool
4. Press 6 to check the status of vmdir if READ_ONLY. If yes, go to the next step. Otherwise, stop here and issue does not match this Knowledge Base article.
5. Press 5 and enter NORMAL to set vmdir to NORMAL state
6. Press 0 to exit the tool.
7. Restart vmdird service.
   service-control --restart vmdird
8. Add ESXi host to vCenter

Additional Information

Unable to add an upgraded host to vCenter/cluster with error "cannot complete the license assignment operation. license service on server is unavailable"