vCenter server Patch Error: "Exception occurred in install precheck phase"

Products

• VMware vCenter Server

Issue/Introduction

• vCenter Server Patch Fails During Precheck Phase or Before RPM Installation with error: "Exception occurred in install precheck phase"

• During the update check in VAMI, the process fails with the message: “Package discrepancy error. Cannot resume!”

Environment

VMware vCenter Server 7.x

VMware vCenter Server 8.x

Cause

During the staging phase of update cycle, not all files required for update are downloaded just in time and the race conditions which will lead to overwriting of certain files essential for the patch process.

Resolution

Workaround:

If the patching process fails prior to RPM installation, apply the following workaround:

1. Take a snapshot of the vCenter Server virtual machine.

2. Access the vCenter via putty session.

3. Download the cleanup script KB_83145_PatchCleanupScript.sh from the Attachments section of this KB article and place it in the root directory of the VC.

4. Assign executable permissions to the script by running:

   chmod +x KB_83145_PatchCleanupScript.sh

5. Execute the script using:

   ./KB_83145_PatchCleanupScript.sh

6. Once the script completes, open the VAMI interface by navigating to: https://<VC_IP or VC_FQDN>:5480

7. Go to Update > Check Updates, and select the desired target update from the list.

    NOTE - Allow the update list to load fully. Do not click "Refresh."

8. Proceed with the upgrade by selecting either "Stage" or "Stage and Install".

        Note: Ensure there is valid backup/offline snapshot of the VCSA prior to implementing the workaround. Refer to VMware vCenter in Enhanced Linked Mode pre-changes snapshot (online or offline) best practice 

1.