Backup fails because ERROR: Cannot access path to backup: "/mnt/urbackup_snaps

client
1

Hi,

One of our machines suddenly stopped working when building the file list, we get an error that he cannot find a specific snapshot directory.

Any ideas how it can be fixed?

Thank you!

Best Regards
Fredrik

Server = 2.4.15 running at Debian 11
Urbackup client = 2.4.11 running at debian 10

Server log =>

2022-02-15 13:32 INFO Starting unscheduled incremental file backup…
2022-02-15 13:32 DEBUG SRV10: Doing backup with hashes…
2022-02-15 13:32 DEBUG SRV10: Doing backup with intra file diffs…
2022-02-15 13:32 DEBUG SRV10: Connecting for filelist…
2022-02-15 13:32 DEBUG SRV10: Waiting for filelist
2022-02-15 13:32 DEBUG SRV10: Connecting for filelist (async)…
2022-02-15 13:48 INFO Snapshotting device /dev/xvdc1 via dattobd…
2022-02-15 13:48 INFO Using /dev/datto2…
2022-02-15 13:48 INFO Mounting /dev/mapper/wsnap-c35c9103338801c2fc0fae010e8b7743b51dd6e7d32c64ae…
2022-02-15 13:48 INFO Indexing of “backup” done. 201 filesystem lookups 0 db lookups and 1 db updates
2022-02-15 13:48 ERROR Cannot access path to backup: “/mnt/urbackup_snaps/c35c9103338801c2fc0fae010e8b7743b51dd6e7d32c64ae/s” Errorcode: 2 - No such file or directory
2022-02-15 13:48 INFO Unmounting /dev/datto0 at /mnt/urbackup_snaps/da91291f4b3f8ed835ff5bc0fc4a321bc70fcb727f53818f…
2022-02-15 13:48 INFO Removing devicemapper snapshot…
2022-02-15 13:48 INFO Destroying dattobd snapshot /dev/datto0…
2022-02-15 13:48 INFO Unmounting /dev/datto1 at /mnt/urbackup_snaps/21665e302228441bef1445a3b0bfb9b8a6425ab9cde42e49…
2022-02-15 13:48 INFO Removing devicemapper snapshot…
2022-02-15 13:48 INFO Destroying dattobd snapshot /dev/datto1…
2022-02-15 13:48 INFO Unmounting /dev/datto2 at /mnt/urbackup_snaps/c35c9103338801c2fc0fae010e8b7743b51dd6e7d32c64ae…
2022-02-15 13:48 INFO Removing devicemapper snapshot…
2022-02-15 13:48 INFO Destroying dattobd snapshot /dev/datto2…
2022-02-15 13:48 ERROR Indexing files failed, because of error
2022-02-15 13:48 ERROR Constructing of filelist of “SRV10” failed: error - index error
2022-02-15 13:48 ERROR Backup had an early error. Deleting partial backup.

This is the end of the urbackup client log in DEBUG =>
[…]
0-1645011079-Following symbolic link at “/etc/systemd/system/timers.target.wants/man-db.timer” to “/lib/systemd/system/man-db.timer” confirms symlink backup target “.symlink_man-db.timer” to “/lib/systemd/system/man-db.timer”
0-1645011079-Following symbolic link at “/etc/systemd/system/timers.target.wants/phpsessionclean.timer” to “/lib/systemd/system/phpsessionclean.timer” confirms symlink backup target “.symlink_phpsessionclean.timer” to “/lib/systemd/system/phpsessionclean.timer”
0-1645011079-Indexing of “etc” done. 403 filesystem lookups 0 db lookups and 2 db updates
0-1645011079-Snapshotting device /dev/xvdb1 via dattobd…
0-1645011079-Using /dev/datto1…
0-1645011079-Mounting /dev/mapper/wsnap-852335dd9556d73a064342571087efdc880ab0caf9c16ae8…
0-1645011079-Indexing of “www” done. 140623 filesystem lookups 0 db lookups and 22 db updates
0-1645011079-Snapshotting device /dev/xvdc1 via dattobd…
0-1645011079-Using /dev/datto2…
0-1645011079-Mounting /dev/mapper/wsnap-3f4f971dc31bae73a7a87741aa046b3e993377b0137f3546…
0-1645011079-Indexing of “backup” done. 201 filesystem lookups 0 db lookups and 1 db updates
2-1645011079-Cannot access path to backup: “/mnt/urbackup_snaps/3f4f971dc31bae73a7a87741aa046b3e993377b0137f3546/s” Errorcode: 2 - No such file or directory
0-1645011079-Unmounting /dev/datto0 at /mnt/urbackup_snaps/0dca06c8ab829f6cda355d63038795b1a0dc1e30c5b0254e…
0-1645011079-Removing devicemapper snapshot…
0-1645011079-Destroying dattobd snapshot /dev/datto0…
0-1645011079-Unmounting /dev/datto1 at /mnt/urbackup_snaps/852335dd9556d73a064342571087efdc880ab0caf9c16ae8…
0-1645011079-Removing devicemapper snapshot…
0-1645011079-Destroying dattobd snapshot /dev/datto1…
0-1645011079-Unmounting /dev/datto2 at /mnt/urbackup_snaps/3f4f971dc31bae73a7a87741aa046b3e993377b0137f3546…
0-1645011079-Removing devicemapper snapshot…
0-1645011079-Destroying dattobd snapshot /dev/datto2…
2-1645011079-Indexing files failed, because of error
2-1645011079-Constructing of filelist of “SRV10” failed: error - index error
2-1645011089-Backup had an early error. Deleting partial backup.
2022-02-16 12:31:30: rc=0 hasError=true state=0
2022-02-16 12:31:30: SERVICE_COMMANDS finished

root@SRV10:/dev/mapper# ls -al
total 0
drwxr-xr-x 2 root root 60 Feb 16 12:31 .
drwxr-xr-x 18 root root 3580 Feb 16 12:31 …
crw------- 1 root root 10, 236 Jan 29 02:06 control

root@SRV10:/mnt/urbackup_snaps# ls -al
total 8
drwxr-xr-x 2 root root 4096 Feb 16 12:31 .
drwxr-xr-x 4 root root 4096 Aug 7 2020 …

2

I temporarily found and solved the problem but I think it must be fixed in the client or dattobd script, I don’t know what the urbackup client send to /usr/local/share/urbackup/dattobd_create_filesystem_snapshot but something goes wrong when he list or run the snapshots due to /var/backups being in the backup-path as described below:

Cause =>

  • /var is mounted from a separate device

  • /var/backup is mounted from a separate device and is in the backup-path

  • /var/backups is a folder residing on /var and is in the backup-path

Temporarily solution =

  • Remove /var/backups from the backup-path.

Thank you!