[LON-CAPA-admin] Database backup?

[Neubauer, Paul]

Hi all, 
 
We (Ball State U) are planning a hardware upgrade (among other things) and in the planning phase, the question of backups arose. 

As I understand it, Lon-Capa uses a MySQL database, but we have normally been doing our backups without shutting down the Lon-Capa software. That is, we basically just copy off the files to our backup system. However, if the database is running at the time, it would seem that we would be vulnerable to cases where changes might occur within the database that would not be backed up. For some inexplicable reason this question had escaped me for all these years.

Where is/are the database datafile(s?) located? I see (using find /home/ -name "*.db") that there are a huge number of .db files on our server. Are these files usually quiescent and used only for the individual users' activity? If so, that would minimze the vulnerability of the overall system to just the data related to the actual users logged on at the time of the backup, but I'm still not really comfortable with that.

Does anyone have any recommendations on backing up the database?

I once administered a different system with a database where we would shut down nightly (at about 3am) to copy the database files so we could get a reliable snapshot of the system at a point in time. Should I plan on doing that to our Lon-Capa system? If not, why not? That is, am I missing something that makes backup safe even while the system is running? 

We have not YET had a backup problem with Lon-Capa, but it seems nearly inevitable that someday backups will be needed and I would prefer that when that day comes, we will have a trustworthy backup to restore.

Thanks,
Paul

Paul Neubauer
Sr. Systems Support Consultant
University Computing Services
Ball State University
Muncie, IN 47306 USA
(765)285-1936
pneubauer at bsu.edu