I am using Duplicati - 2.0.5.1_beta_2020-01-18
Duplicati is running in a FreeNAS Jail backing up to an NFS Share on another Synology.
To get around permission issues I mount the target from the FreeNAS box and then mount the FreeNAS mounts from the Jail.
The trouble is that from time to time the target isn’t available when I boot the FreeNAS (I have an issue with FreeNAS I am trying to track down) so the mounts don’t happen from FreeNAS. This results in corrupted databases (for all 9 backup jobs - so this isn’t a one off)
Is there a way to check for the existence of the backup files before attempting the backup and if the files aren’t there then fail the backup (but without corrupting the database)
Normally if the target isn’t accessible Duplicati will fail the backup job with a “remote files missing” error. It shouldn’t corrupt any job databases. Where are the databases stored? The FreeNAS host, right?
Also, Synology supports a lot of protocols so you may be able to simplify by not using NFS. WebDAV and SFTP don’t require any “mount” process. Just an idea!
It’s a bad idea to store data you want to keep inside the container, is it not? It is with Docker. Containers are designed to be disposed/recreated easily. Not sure if that is part of your issue or not.
FreeNAS jail is analogous to a docker container (from what I understand). If you delete the jail, you lose your Duplicati configs and databases. In my docker container I redirect those folders so the Duplicati databases are stored on the host.
In any case I think it’s probably irrelevant to your main issue.
Is it possible for you to try some other protocol other than NFS when saving to your target NAS, at least as a test?
Ok, but FTP is one of the more unreliable ones. SFTP (SSH) would be better if you want to stick with the FTP family. Otherwise I find WebDAV very reliable on my Synology.
Mostly due to the formatting differences used with directory listings (among various FTP servers). We see issues now and then with people having compatibility issues. Sometimes using the “FTP Alternative” back end helps. If it is working reliably for you, then there’s probably no harm in continuing to use it.