vCenter patching or upgrade might fail with the error "Exception occured in postInstallHook for vmdir:Patch. Please check the logs for more details. Take corrective action and then resume.""

Products

• VMware vCenter Server

Issue/Introduction

- Updating the vCenter via VAMI fails with the error "Exception occured in postInstallHook for vmdir:Patch. Please check the logs for more details. Take corrective action and then resume."

- We may see that all the services would be running fine. 

Cause

This might happen if the /etc/hosts file has incorrect format or entries. 

Resolution

Note: Please ensure to take a backup of the vCenter before making any changes. 

• Edit the /etc/hosts file using the VI editor and correct the content of the file in the below format. 

# Begin /etc/hosts (network card version)

# VAMI_EDIT_BEGIN
# Generated by Studio VAMI service. Do not modify manually.
127.0.0.1 vCenter_FQDN vCenter_shortname localhost
::1 vCenter_FQDN vCenter_shortname localhost ipv6-localhost ipv6-loopback
# VAMI_EDIT_END

• Save the file and restart all the services. 
• Ensure that the DNS resolutions have the correct IP and FQDN of the vCenter server 
• Attempt to start the patching again.