Lock errors in Sync job during Verify job running

[rahman]

Hi,

Is it normal to get bellow error in a Sync (pull) job when also a Verify job running on the same datastore?

2026-05-16T09:00:14+03:00: [vm/164]: sync group vm/164 failed - 2026-05-15T22:00:43Z: while creating locked snapshot 'BackupDir { store: "default", ns: BackupNamespace { inner: ["default"], len: 7 }, dir: BackupDir { group: BackupGroup { ty: Vm, id: "164" }, time: 1778882443 }, backup_time_string: "2026-05-15T22:00:43Z" }': unable to acquire snapshot lock "/run/proxmox-backup/locks/default/default/vm-164-2026\\x2d05\\x2d15T22\\x3a00\\x3a43Z": Unable to acquire lock "/run/proxmox-backup/locks/default/default/vm-164-2026\\x2d05\\x2d15T22\\x3a00\\x3a43Z" - Resource temporarily unavailable (os error 11)

I get this error in a Sync (pull) job on PBS1/default datastore which pulls from PBS/default datastore. There were running Verify Job on both PBS1 and PBS2.

Regards,

Rahman

 

[fabian]

yes, it is possible that such an error occurs if concurrent actions/tasks are preventing snapshot creation.

 

[rahman]

yes, it is possible that such an error occurs if concurrent actions/tasks are preventing snapshot creation.

OK, but the verify jobs are read-only jobs, they don't create any snapshot etc, so why does it prevent creation of a snapshot an only one but all? As you can see in the attached job logs, the sync job does its job for the other snapshots without any problem, even the Verify job was still running. So should this be improved? Maybe Verify jobs does not randomly block creation of a snapshot? Or Sync jobs should handle this temporary situation, wait and retry?

Rahman

 

[fabian]

https://bugzilla.proxmox.com/show_bug.cgi?id=4523