XCP-NG backup failing - The snapshot chain is too long

[czopper]

1/30/2026 12:07:17 AM :: HVFS01 : Failed to perform backup: [TBD] Task a4cb9b82-3138-ea91-19d8-f152d2c21b92 (Async.VM.snapshot) failed: . SR_BACKEND_FAILURE_109. . The snapshot chain is too long.

Any thoughts on getting past this?

[Mildur]

Hi Richard,

As indicated in the error message, I would first delete the VM snapshots on Proxmox.
If that doesn’t help, please contact our support team.

Best,
Fabian

[cody.ault]

Based on the error, if you can't clear the snapshots, it might be worth reaching out to Vates to check on the health of the VM. We rely on checkpoints to take backups but they should be cleaned up. I can reach out to collect logs to see if we're seeing any error messages on the cleanup process on our side but the hypervisor vendor might be needed as well to cleanup the VM safely.