In Moodle you can choose to have your course automated backup storage in the course backup area and/or in a specified directory.
I would like to know if Moodle handles files equal for course backup files as for user files, in a Unix-like way, we could call it with Moodle hard links? Or do you double up your hard disk usage for backup files if you choose both a custom directory and the course backup area?
You double it. The idea is to have an alternative location such as an external server for the custom directory.
Well, that is my presumption - pretty sure it is correct but just realized as I wrote that that I am not 100% certain, probably 90% certain!
I am afraid you are right, that was my first thought too, I just wanted to keep the hope.
IF am understanding, would agree with Emma ... doubles.
However, what does "in a Unix-like way" mean? Do you mean like rsync? IF you are thinking in terms of rsync, the answer would be no ... backups are an archive - tar.gz and the only way to get rsync like behavior with those is (am thinking ... have never done it) to open the tar.gz and replace only those files that have changed in the archive and then re-archive it. If that could be done then the backups would/could either shrink or grow (most grow, I would imagine). While some files in a backup are compressed and thus save space, digital type files ... like videos ... won't get much compression. Plus, the un-archiving would/might require most of the free space ... depending.
I have a preference (due to experiences with various systems that developed problems with the new file system in vr 2->) .... autobackups go to a designated directory where I can easily see their filename and size + the number of backups. Autobackups to the file system presents a potential issue with DB matching what's physically present in filedir (sea). That's not supposed to happen but it has! Autobackups also might fail due to the shear size of the course ... digital photography .... video editing ... etc. Help with one system that has such courses and checked on it the other day ... one course began this year as a 50 Gig backup ... it's nearing semester now and the backup is 90+ Gig and by the break will be over 100 Gig (have never really tried to restore such a course ... and am imagining there might be issues attempting that via GUI interface.
Some might have 'unlimited' space (if there is such a thing), but many don't. The very last thing one needs to happen is for the drive/partition upon which the DB files reside running out of disk space due to run away auto backups that one can't find without a DB in the 'sea of files'.
My 2 cents, of course!
'spirit of sharing', Ken
What I meant with unix-like was that Moodle do not store a file twice unless it is necessary or you force it to. Moodle links to the original file instead.
Thanks for sharing possible issues with autobakups, I better be aware of that.