Backup fails with disk errors but I can't find any disk error

Hi…

I have recently returned to using Urbackup but I am getting random disk error fails about 1 in every 4 backups across 5 different clients. It is not the same file each time.

Setup - Debian 10, backup is help on RAID 1 BTRFS array. urbackupsvr = 2.5.28, clients 2.5.21 & 2.5.22

I have tried

  • clearing the whole backup set and starting over (I ran remove unknown afterwards)
  • reformatting the disks
  • removing and reinstalling clients and server.

BTRFS device stats reports zero errors and the drive has been scrubbed without errors being reported. syslog does not report any disk errors or issues.

any ideas on what might be causing this?

Errors 15/02/23 17:54 Writing metadata to /media/backup/Wills-PC/230215 754/.hashes/willl/AppData/Local/BraveSoftware/Brave-Browser/User Data/Default/History failed
Info
15/02/23 17:54
Waiting for file hashing and copying threads…
Info
15/02/23 17:55
Writing new file list…
Errors
15/02/23 17:55
Fatal error during backup. Backup not completed
Info
15/02/23 17:55
Transferred 43.3373 MB - Average speed: 79.168 MBit/s
Errors
15/02/23 17:56
FATAL: Backup failed because of disk problems (see previous messages)
Info
15/02/23 17:56
Time taken for backing up client Wills-PC: 1m 30s
Errors
15/02/23 17:56
Backup failed

Check permissions on the backup path. Also, check the permissions on the urbackup server folder.