(Just to know if I should wait a bit or go with the first solution)
Are you planning to add a server-backup service task in the near future?
One solution is to shut-down the server and than do the backup (which won't work if you're running from a service task).
Another solution is to back-up the various database components using their respective CLIs (using mongo client for MongoDB, for example) and/or backup policies (each one has a different method for online backup that does not require services shut down).
Will that work? Is it possible that while creating the zip archive, one file gets corrupted (because it was being written by trains-server (redis, ES, etc.)
That's exactly the problem 🙂
It's not something we're planning in the near future 🙂
Ok, I won't have time to venture to check the different database components, the first option (shuting down the server) sounds like the easiest option for me, I would then run manually the script once a month or so