Hi !
I used UrBackup für a long time on an QNAP NAS with QTS (linux) on ext4. I used docker pull uroni/urbackup-server:latest.
Now I switched to a QNAP NAS with QTShero (linux) on zfs. Here I also used docker pull uroni/urbackup-server:latest (not docker pull uroni/urbackup-server:latest-zfs which I saw later).
I applied the lines as stated here to my compose.yml
devices:
- /dev/zfs:/dev/zfs
But I always have errors that result in database crash and so I have to re-setup everything.
After a database crash I usually get this error: ERROR: Error preparing Query [PRAGMA cache_size = -2048]: SQL logic error
In the log before the crash there is : Files WAL file urbackup/backup_server_files.db-wal greater than 1000 MB. Doing full WAL checkpoint… Full checkpoint of urbackup/backup_server_files.db-wal done.
After a docker restart the I receive the PRAGMA error (above) and everything is broken.
Does anyone know what could cause this and what I could do against it ?
The block size of the share where the database lives is 128k.
Now my actual next try is skipping the ZFS-thing - so I suppose it will work as normal - and hope it will not break the database again …
btw:
What would be my benefits when using the /dev/zfs directive in compose.yml ?
Just the copy on write snapshots ?
Will the underlying ZFS also dedup and compress if not using the ZFS directive ? (I guess yes) and do I need to work with datasets ?
On QTS i have to use the given storage pool.
root@NAS:/# urbackup_snapshot_helper test
Testing for btrfs...
TEST FAILED: Creating test btrfs subvolume failed
Testing for zfs...
TEST FAILED: Dataset is not set via /etc/urbackup/dataset
so I think it’s useless to use the ZFS-image on a NAS ?
Seems like it’s similar or identical to the issue described here.
I think it is mmap error 19 ENODEV which probably means that the -shm file is on file system which does not support mmaped files. Move it to a file system that supports this and it should be fixed…
I consider moving from QTShero to QTS (which comes without ZFS but with ext4 and worked beforehand)
Just came across this topic.
For anyone else finding this, QTShero does not use use your “normal” ZFS. QTShero ussage a fork of a very old version of openZFS. Which now does not comply with any normal ZFS standards. also QTShero ussage a very strange partition layout regarding ZFS. it is best to not touch it and ignore that it is using ZFS underneat (Which frankly it doesnt really do at this point.)