Syncing safely to NAS

[KayDav]

I know it is not recommended to keep the Calibre library on a NAS because it may (will?) lead to a corrupt database. I'd like to check whether there are any flaws with the sync/backup plan I have come up with.

I keep my Calibre library on a SD card which usually resides in my laptop. At the moment my NAS software is set to sync the contents of the SD card to the NAS (in one direction from card to NAS, the NAS does not alter the contents of the card). I take the precaution of pausing the sync software whenever I am working in Calibre, then when I have quit Calibre I restart the sync to update the NAS. I also make manual backups by saving books to disc using Calibre.

Does this method avoid the potential database corruption that we are warned of?

[ownedbycats]

I believe this is actually the usual advice for running Calibre with cloud sync (Dropbox, OneDrive, etc); run the local copy then sync it over. I don't see why it won't work with NAS.

[KayDav]

Thank you, I was worried that I'd missed a flaw or misunderstood what I'm trying to protect my database from.

[rantanplan]

Manual sync is not a problem at all (e.g. via Robocopy/rsync etc), only syncing via Onedrive/Gdrive/Dropbox/etc might lead to problems due to file locking etc.

Putting the Calibre library on a NAS might lead to problems if the DB is accessed by multiple users at the same time. It's also not recommended using Calibre and calibre-web on the same DB at the same time.

[theducks]

OneWay sync (make a shadow copy) is fine to a NAS.

Two way can be a disaster, as there could be a 'race condition', where the DB and the actual book files get out of version order.

NEVER sync with Calibre/Server Running (Library changes won't happen if you are not using it)
I use Free file Sync. It takes ~3 Min to scan for changes and 1 to write the files updated.

FWIW Google drive messes with file names (uses something that looks like what C does for {id} . That = disaster)

[KayDav]

That's good to know, thank you. I am definitely only doing one-way sync, basically as an automated backup. And have a sticky note on my laptop to remind me to switch sync off while I'm databasing

[ownedbycats]

Originally Posted by theducks

FWIW Google drive messes with file names (uses something that looks like what C does for {id} . That = disaster)

Specifically, GDrive uses the (#) for their versioning, so it will strip those from the directory names and break Calibre.