vCenter patch installation fails with "Installation failed" error

Products

• VMware vCenter Server

Issue/Introduction

When  attempting  to apply the most recent patch to the VMware vCenter Server via the command line, the update halts and outputs the following error:

Installation failed. Please collect the VC support.

The patch installation failure is corroborated by the following log snippets and error messages, which indicate a failure to communicate with the directory service:

ERROR vmdir Unable to retrieve VMDir state of the vCenter <Other Vcenter in ELM>
 
vmdir:CollectRequirements ERROR vmdir Unable to retrieve VMDir state of the vCenter <Vcenter in ELM>.
 
vmdir:CollectRequirements ERROR vmdir_validator dir-cli failed. Error 382312502: Failed to connect to the remote host, reason = rpc_s_connection_closed (0x16c9a036).

Environment

VMware vCenter Server 8.x
VMware vCenter Server 7.x

Cause

This issue is caused by a firewall rule actively blocking communication attempts on port 2012 between the vCenter nodes. Command execution initially hangs without response due to the blocked port, leading to the rpc_s_connection_closed failure during the patch installation.

Resolution

To resolve this issue, open port 2012 on the firewall between the vCenter nodes to permit the required directory service communication.

1. Open port 2012 on the firewall between the VMware vCenter nodes.

2. Verify that the connection is successful by running the following command:

         root@vcenter [ ~ ]#  nc -zv <Vcenter FQDN or ip in ELM  > 2012

         root@vcenter [ ~ ]# /usr/lib/vmware-vmafd/bin/dir-cli state get --server-name <Vcenter FQDN or IP in ELM>

         Should  return   the status  if the port is open   Directory Server State: Normal (3)

     3.  Re-attempt the patch application.