> > > > Hi all, > > > > I have a question as to how cpool stores it's information. > > > > I have everything running good with my backup system, but now I want to > > rsync all or /var/lib/backuppc to an external hard drive for an offsite > > backup. > > When I run the rsync, everything syncs fine except the cpool directory. > > If I do a du on /var/lib/backuppc/cpool it's size is 3.8 GB. If I do it > > on me external device, the size is 104 GB. So I keep running out of > > disk space on my external drive. How do I keep the sizes the same? > > the cpool (or the pool, if you're not using compression) makes heavy > use of hardlinks in order to avoid storing duplicate copies of > identical files. rsync, by default, will not preserve hardlinks -- so > your external copy is getting multiple copies of the identical files > that backuppc tried to consolidate. you can tell rsync to preserve > the hardlinks, but you won't be happy -- your copy will now take > days, instead of hours or minutes, and you may run out of memory. > > there's no perfect way to make a copy of the pool. the best is > to do a byte-for-byte copy, either to an identical hard-drive, or > by using software RAID as a syncing mechanism for your two disks. > (i.e., run as a "broken" RAID pair most of the time, and only add > the second half when you want to do your external copy.) this, and > other tricks, have been extensively covered in the archives. if > there were a FAQ section in the backuppc documentation (i don't think > there is), this would be question #1.
If you are simply copying the pool, why not try "cp -a". It preserves hardlinks (at least in Linux), and probably doesn't require as much memory as rsync does. You don't get the smart copy-only-what-has-changed behavior, but if it's faster, it's faster. Just an idea, and perhaps simpler than using RAID. I confess I haven't searched the archives to see if anybody has suggested cp in the past :-) Bernardo ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click _______________________________________________ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
