[Box Backup] databases

[Ben Summers]

On 12 Feb 2004, at 10:00, Bo Rasmussen wrote:

> Hey,
>
> Just to let you know Ben, that I have successfully completed a setup
> with a FreeBSD 4.8 client backing up around 1GB data to a OpenBSD 3.4
> server, I will let you know if there is any problems.

Good news!

>
> BTW. Ben, should there be any problems backing up open or closed mysql 
> databases
> with the lastest 0.03 version ? I can't seem to find any clues 
> regarding this.

Closed -- not a problem.

Open -- depends.

All backup systems have problems with files being modified while 
they're being backed up. MySQL should be able to repair any damage 
caused by this, but it's not an ideal solution.

I am intending to have code which detects writes during a backup 
operation, and aborts if changes have been made. This should avoid the 
problem, but again, is not ideal. (Expect this in the next version.)

The best solution with MySQL, if you have the disc space, is not to 
back up the databases directly. Instead, do a mysqldump of the entire 
database into a file with a cron job, and back up the dumps instead. 
This will result in less disc space needed for the backup because 
you'll only be backing up the data, not the indices.

But as I said, this problem is common to all backup systems. But 
because of the nature of Box Backup, I'm going to take extra 
precautions and detect changes.

Thanks for trying it out.

Ben