first of all my Environment:
XCP-NG 7.6 Pool (4 Members)
Shared (LVM) Block-Storage (FC and iSCSI)
XenOrchestra (from sources, 5.42.1 on Ubuntu 18).
Backup-Remote via NFS.
Nightly Delta Backup 00:30 - Retention 8
From time to time i have the problem of getting an Error on one or more VMs in my Delta-Backup-Job.
Error (example): "invalid header checksum 1143961443, expected 4294883451"
I have seen this over the last few Months about 10 to 15 Times on different VMs.
(a working solution is to delete/move the existing backups of this VM, so it starts with a new full one)
After some investigation we now found the cause of the problem.
Whenever we resize one or more disks of a VM, all looks good for that moment.
But when the retention Limit is reached, the Backup of the VM(s) with a former resized Disk will fail with error "invalid header checksum".
All later Backups will even fail, so the existing Backups will remain from the day of the resize till the reach of retention.
(in my case, Retention 8. The VM today shows 8 restorable Backups from 01.06. to 08.06. - The Disk was resized on 31.05.)
Does anyone else expieriance the same Problem?
Might this be an exeption that is simply not intended?
Or could it be that i missed some dependencies in my from source built?