Error Backup Server

[Dexter23]

Hi everyone first time experience this type of error on PBS, after quick search is possible related to ram error as far as i understand.

The Host is a Fujitsu Esprimo with 2x4gb of ram non-ecc.

I can try remove the incrimanted backup and see if the next goes fine?

ERROR: backup write data failed: command error: write_data upload error: pipelined request failed: detected chunk with wrong digest.
103: 2026-02-15 21:57:58 INFO: aborting backup job
103: 2026-02-15 21:57:58 INFO: resuming VM again
103: 2026-02-15 21:57:58 ERROR: Backup of VM 103 failed - backup write data failed: command error: write_data upload error: pipelined request failed: detected chunk with wrong digest.

 

[Chris]

Hi,

I can try remove the incrimanted backup and see if the next goes fine?

what do you mean by this? The backup snapshot which fails will already be removed, the previous backup snapshot should be successful (you can run a verification on it to double check, but only once you have excluded bad RAM).

103: 2026-02-15 21:57:58 ERROR: Backup of VM 103 failed - backup write data failed: command error: write_data upload error: pipelined request failed: detected chunk with wrong digest.

This error happens on upload, so the chunk data the PBS server receives does not match the expected digest. Most likely is data corruption occuring either on the PBS host when receiving the data or the PVE client while chunking and/or sending the data chunk.

 

[Dexter23]

Hi,

what do you mean by this? The backup snapshot which fails will already be removed, the previous backup snapshot should be successful (you can run a verification on it to double check, but only once you have excluded bad RAM).


This error happens on upload, so the chunk data the PBS server receives does not match the expected digest. Most likely is data corruption occuring either on the PBS host when receiving the data or the PVE client while chunking and/or sending the data chunk.

I mean that i remove manually the backup on the PBS which have the verify state failed, this night the backup was succeed from the pve:

103: 2026-02-17 22:53:33 INFO:  99% (1.5 TiB of 1.5 TiB) in 1h 53m 30s, read: 138.1 MiB/s, write: 3.0 MiB/s
103: 2026-02-17 22:53:40 INFO: 100% (1.5 TiB of 1.5 TiB) in 1h 53m 37s, read: 2.1 GiB/s, write: 2.9 MiB/s
103: 2026-02-17 22:53:40 INFO: backup is sparse: 592.46 GiB (39%) total zero data
103: 2026-02-17 22:53:40 INFO: backup was done incrementally, reused 1.45 TiB (98%)
103: 2026-02-17 22:53:40 INFO: transferred 1.46 TiB in 6817 seconds (225.3 MiB/s)
103: 2026-02-17 22:53:40 INFO: adding notes to backup
103: 2026-02-17 22:53:40 INFO: Finished Backup of VM 103 (01:53:38)

But on the PBS the verify process on this backup has failed, so it means that the problem is on PBS side?

Job ID:    v-cb28e9e8-e2a0
Datastore: zpool01

Verification failed on these snapshots/groups:

    vm/103/2026-02-17T20:00:02Z

If yes the 1st step is to check the RAM? As i said this is non-ecc ram installed on Fujitsu Esprimo Desktop.
Thanks.