existing bitmap was invalid and has been cleared - only 1 backup server

[felipe]

Hi,

we got the message:
INFO: backup mode: snapshot
INFO: ionice priority: 7
INFO: creating Proxmox Backup Server archive 'vm/200/2021-05-05T00:26:06Z'
INFO: issuing guest-agent 'fs-freeze' command
INFO: enabling encryption
INFO: issuing guest-agent 'fs-thaw' command
INFO: started backup task '7057d84c-cf21-4ac2-9569-0861546a3ba8'
INFO: resuming VM again
INFO: efidisk0: dirty-bitmap status: OK (drive clean)
INFO: virtio0: dirty-bitmap status: OK (5.4 GiB of 80.0 GiB dirty)
INFO: virtio1: dirty-bitmap status: existing bitmap was invalid and has been cleared

so suddently one out of 3 disks was invalid. no other backup server in use anymore. it worked for 2 weeks without problem. no restart of vm or move to another server.

pveversion:
pve-manager/6.3-6/2184247e (running kernel: 5.4.106-1-pve)

 

[Stefan_R]

The bitmap is validated against the latest snapshot in the VMs backup group only. If it doesn't contain the drive (i.e. you made a backup with only the other drive and efidisk), this can occur. Alternatively, if you have deleted or pruned the latest snapshot(s), this can also happen, but only if the first drive's checksum still matches the latest snapshot's after any deletions (i.e. it was unmodified for two or more backups in a row).

In general, a cleared bitmap is not a hard error, the backup will simply fall back to do doing a full read. Can you reproduce the issue in your environment?