VCSA VAMI Backups Failing with “Backup Manager Encountered an Exception”

Products

• VMware vCenter Server

Issue/Introduction

Both scheduled and manual VCSA backups initiated through the VAMI interface were failing with the error: “Backup Manager encountered an exception.”

Review of backup.log confirmed the failure was occurring after successful completion of the Postgres schema dump and component script execution.

INFO: Successfully dump Postgres schema data. INFO: Successfully dumped data for multiple tables.

Warnings related to circular foreign-key constraints were noted but are non-blocking and did not prevent the backup from proceeding:

pg_dump: warning: there are circular foreign-key constraints on this table: vpx_entity, pm_config_commits pg_dump: You might not be able to restore the dump without using --disable-triggers...

 

No additional errors were observed in the logs or UI, indicating that the failure was happening during the post-dump phase—specifically when writing or transferring the backup archive.

Environment

vCenter 7.x, 8.x 

Cause

The cause of the failure was insufficient disk space on the external backup target.

Although the VCSA was able to perform the internal operations (schema dump, table data export), the backup process failed when attempting to write the archive to the destination path due to storage constraints.

Resolution

Old backup files were manually deleted from the backup target to free up space. After reclaiming disk capacity, both manual and scheduled backups succeeded without any additional changes to the VCSA configuration.

Recommendations to avoid recurrence:

• Regularly monitor and purge obsolete backups on the external backup target.

• Set up disk usage alerts on the backup server to catch low-space conditions in advance.

• Optionally configure backups to a larger or secondary target if frequent retention is required.