How to Safely Perform Snapshot Rollback of Veeam Backup for Microsoft 365

Prerequisites and Restrictions

• Before reverting the snapshot:
  • All jobs and restore tasks must be fully stopped and disabled.
  • All NATS streams must be removed/cleaned to avoid metadata conflicts.
  • All Veeam Backup for Microsoft 365 components (controller, proxies, PostgreSQL, and NATS) must be fully shut down.
• Never connect a PostgreSQL database used with a higher Veeam Backup for Microsoft 365 version to a lower Veeam Backup for Microsoft 365 version — this can cause repository corruption and schema mismatches.

Step-by-Step Rollback Procedure

Part 1: Preparation and Shutdown

1. Stop all Veeam Backup for Microsoft 365 components:
   • Controller service (Veeam.Archiver.Service)
   • All proxy servers (Veeam.Archiver.Proxy)
   • REST service (Veeam.Archiver.REST.Service)
   • Update service (Veeam.Archiver.Update.Service)
   • PostgreSQL server
   • NATS server
      

Part 2: Environment Drain and NATS Stream Cleanup

2. Stop and disable all jobs, and ensure all restore tasks have stopped.
3. Remove or clean all NATS streams.
   
   For example, delete the contents of the folder:
   C:\ProgramData\Veeam\Backup365\nats\jetstream\$G
    

Part 3: Snapshot Reversion

4. Revert the environment to the snapshot created prior to the update.
   
   Tip: If you are reading this article before creating the original snapshot, Veeam recommends stopping all Veeam Backup for Microsoft 365 services before creating that original snapshot.
    

Part 4: Post-Rollback Startup Sequence (Strict Order)

5. Start the PostgreSQL server.
6. Start the NATS server (ensure all streams are cleaned up).
7. Start the Veeam Backup for Microsoft 365 controller service (it will recreate all required NATS streams).
8. Start the Veeam Backup for Microsoft 365 proxy servers.
   
   The proxies will perform repository synchronization checks. If any repository contains backups or blobs newer than the reverted metadata, the proxies will detect that repository as out-of-sync.