Tino Schwarze wrote: > Hi Bowie, > > On Wed, Feb 18, 2009 at 12:26:16PM -0500, Bowie Bailey wrote: > > > > So, given that, I don't really understand why there is a > > > distinction between a full and an incremental backup. Shouldn't > > > either one take up the same amount of space? That is, if you've > > > got few changes on the client, then on the server you're mostly > > > just hardlinking things anyway, right? So why is there a choice? > > > > The result is basically the same, the difference is in > > implementation. A full backup will compare the contents of every > > file on the system to see if anything has changed. An incremental > > will only check files whose change date has been updated since the > > last backup. > > The last sentence is only true for non-rsync transfer methods, e.g. > smb and tar. Rsync will detect any files which have been modified or > added since the last run since it works by comparing file lists > between server and client while samba and tar backup methods depend > on the file's change times to detect changes.
Yea, I wasn't quite sure about that one. I know that an incremental backup with Rsync is so much faster than a full because it doesn't check everything, but I'm a bit fuzzy on the details. > > I believe one of the main incremental backup issues is that they do > > not detect deleted files. Incremental backups are also usually > > MUCH faster than full backups. For example, one of my backups > > takes about 600 minutes for a full backup, but only 56 minutes for > > an incremental. > > Incrementals using rsync will detect deleted files correctly. I'm not > sure about samba/tar. I know that there is something that can get missed by an incremental backup as a result of the way it works, I just don't remember exactly what it is. -- Bowie ------------------------------------------------------------------------------ Open Source Business Conference (OSBC), March 24-25, 2009, San Francisco, CA -OSBC tackles the biggest issue in open source: Open Sourcing the Enterprise -Strategies to boost innovation and cut costs with open source participation -Receive a $600 discount off the registration fee with the source code: SFAD http://p.sf.net/sfu/XcvMzF8H _______________________________________________ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: http://backuppc.wiki.sourceforge.net Project: http://backuppc.sourceforge.net/
