On 12/3/2010 4:14 PM, Adam Tauno Williams wrote: > On Fri, 2010-12-03 at 12:51 -0800, John R Pierce wrote: >> On 12/03/10 12:25 PM, Les Mikesell wrote: >>> Whenever anyone mentions backups, I like to plug the backuppc program >>> (http://backuppc.sourceforge.net/index.html and packaged in EPEL). It >>> uses compression and hardlinks all duplicate files to keep much more >>> history than you'd expect on line with a nice web interface - and does >>> pretty much everything automatically. >> I'm curious how you backup backuppc, like for disaster recovery, > I know nothing about backuppc; I don't use it. But we use rsync with > the same concept for a deduplicated archive. > >> archival, etc? since all the files are in a giant mess of symlinks > No, they are not symbolic links - they are *hard links*. That they are > hard-links is the actual magic. Symbolic links would provide the > automatic deallocation of expires files. > >> (for deduplication) with versioning, I'd have to assume the archive >> volume gets really messy after awhile, and further, something like that >> is pretty darn hard to make a replica of it. > I don't see why; only the archive is deduplicated in this manner, and > it certainly isn't "messy". One simply makes a backup [for us that > means to tape - a disk is not a backup] of the most current snapshot. Actually, making a backup of BackupPC's data pool (or just moving it to new disks) does get messy. With a large pool there are so many hardlinks that rsync has trouble dealing with it, eats all your memory, and takes forever. This is a frequent topic of conversation on the BackupPC list. However, the next major version of BackupPC is supposed to use a different method of deduplication that will not use hardlinks and will be much easier to back up. -- Bowie