File-based backup failing with var/lib/vmware/vmca/certs.db file changed during backup

Products

• VMware vCenter Server

Issue/Introduction

The backup.log in /var/log/vmware/applmgmt contains the following errors:

2024-11-06T01:00:28.355 [20241106-010011-23504390] [ConfigFilesBackup:PID-1023646] [ConfigFiles::BackupConfigFiles:ConfigFiles.py:347] ERROR: Failed configuration files backup
Underlying process status. rc: 1
stdout: 
stderr: /usr/bin/tar: var/lib/vmware/vmca/certs.db: file changed as we read it
/usr/bin/tar: var/lib/vmware/vmca: file changed as we read it
Traceback (most recent call last):
  File "/usr/lib/applmgmt/backup_restore/py/vmware/appliance/backup_restore/components/ConfigFiles.py", line 339, in BackupConfigFiles
    raise BackupRestoreError("Failed configuration files backup",
util.Common.BackupRestoreError: Failed configuration files backup
Underlying process status. rc: 1
stdout: 
stderr: /usr/bin/tar: var/lib/vmware/vmca/certs.db: file changed as we read it
/usr/bin/tar: var/lib/vmware/vmca: file changed as we read it

Environment

VMware vCenter Server 7.x

VMware vCenter Server 8.x 

Cause

This issue occurs when "var/lib/vmware/vmca/certs.db" updates during the execution of tar commands performed in file-based backup.
"var/lib/vmware/vmca/certs.db" is updated when vTPM-enabled VM cloned or created.

This problem is most likely to occur in VDI environments where the VM require vTPM (ex. Win 11) are frequently cloned.

Resolution

Broadcom VCF engineering is aware of this issue and working towards a fix.

Workaround:
To workaround this issue, perform backups during times when vTPM virtual machines are not being created or cloned.