[TriLUG] backup methodology

[Jeremy Portzer]

On Thu, 2003-02-20 at 17:05, Jason Tower wrote:
> as long as it's only a couple of gigs, and it's only moving across the lan, i 
> wouldn't bother with tar/incremental backups unless space on the backup 
> server is really tight.  using the rsync method that jeremy linked to earlier 
> is probably the best bet, or just copy the files directly if you're really 
> lazy like me.  make a seperate directory for each day of the week and use a 
> cron job to copy data to the appropriate directory on the appropriate day.  
> that way if you need to restore a file from three days ago you can do it in 
> about three seconds.  if you have the space for it save the friday 
> directories and rotate them so you always have three or four, that way you 
> can go back a month or so if necessary.

Just to make sure people noticed -- that "rsback" script that I
mentioned (based on the rsync article) does this exact thing -- takes
snapshots for each day, allowing you to access previous versions.  The
nice thing is that it uses hard links for files that haven't changed, so
a lot of space is saved.  And since rsync is used, files that haven't
changed aren't copied, saving time and network bandwidth.  It's really
very easy to set up.   I'm testing this on the TriLUG backup server now.

For even more space savings, look into "rdiff-backup" which only stores
deltas (differences) between files, but it does require a special
utility to recover the files.

--Jeremy