PBS tries to start VMs during backup, not enough ram


Active Member
Mar 25, 2017
I have some VMs on a server which are not started, but are included in the backup. The backup job fails because PBS cannot start the VM because of missing RAM Why does PBS try to start a switched of VM to do a backup? If I temporarily reduce the RAM in the VM config, the backup works fine. This should be be the case and PBS should be able to backup offline VMs not matter how much RAM they need if there were switched on.

Here the log:
INFO: Starting Backup of VM 107 (qemu)
INFO: Backup started at 2020-08-23 07:52:36
INFO: status = stopped
INFO: backup mode: stop
INFO: ionice priority: 7
INFO: VM Name: xxx
INFO: include disk 'scsi0' 'data1:vm-107-disk-0' 120G
INFO: creating Proxmox Backup Server archive 'vm/107/2020-08-23T05:52:36Z'
INFO: starting kvm to execute backup task
kvm: cannot set up guest memory 'pc.ram': Cannot allocate memory
ERROR: Backup of VM 107 failed - start failed: QEMU exited with code 1
INFO: Failed at 2020-08-23 07:52:37
That is indeed a bug, stop mode backups should not require the full RAM allocation. You can open a bug report on our bugzilla if you want, but I'll take a look regardless.


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