Decommissioning a vCenter Server node from an Enhanced Linked Mode (ELM) Single Sign-On (SSO) domain

Products

• VMware vCenter Server

Issue/Introduction

This KB covers the steps to decommission and completely remove a vCenter Server node from a shared Single Sign-On (SSO) domain either for decommissioning hardware, downsizing an environment, or other environmental reasons.

Environment

vCenter Server

Resolution

1. SSH to the vCenter Server that is being decommissioned, as the root user.

2. Make note of the PNID for the vCenter Server that is being decommissioned with the following command:
   
   /usr/lib/vmware-vmdir/bin/vdcrepadmin -f showservers -h localhost -u administrator

3. Power off all vCenter Servers in the ELM group by performing a Guest OS shutdown on the vCenter VMs.

4. Take concurrent, offline, snapshots of all powered off vCenter Servers. This ensures a consistent rollback point for the entire SSO domain. For more information see - VMware vCenter in Enhanced Linked Mode pre-changes snapshot (online or offline) best practice

5. Power up only the vCenter(s) that are not being decommissioned.

6. SSH to one of the vCenter Servers that are not being decommissioned, as the root user.

7. Run the cmsso-util unregister command below to unregister the vCenter Server Appliance that is being decommissioned from the SSO domain:
   
   cmsso-util unregister --node-pnid "vCenterServer_PNID from step 3" --username [email protected]

Note: There is downtime involved in executing the cmsso-util unregister command. It will restart the services on the node where the command was executed.

8. Verify the decommissioned vCenter has been removed by running the following command:
   
   /usr/lib/vmware-vmafd/bin/dir-cli nodes list

9. Delete the decommissioned vCenter Server Appliance.