On Mon, 14 May 2007 11:12:09 -0400, Roberto C. Sánchez wrote: > On Mon, May 14, 2007 at 02:08:56PM +0200, Dan H wrote: >> On Sun, 13 May 2007 20:56:21 -0400 >> Roberto C. Sánchez <[EMAIL PROTECTED]> wrote: >> >> > Good point. What I like about the rsync snapshots is that I can >> > "browse" back in time. In my case, I always have hourly snapshots >> > going back four hours, daily snapshots going back four days and weekly >> > snapshots going back four weeks. That works out rather nicely in that >> > it is trivial for me to compare files across snapshots. >> >> That sounds nice but how does it work? I only use rsync to keep exact >> mirrors of directory trees in sync, but have never heard about the >> history thingy. >> > If you read "Easy Automated Snapshot-Style Backupse with Rsync" [0], > it will walk you through the process of setting up rsync to use > hardlinks to create the snapshots. That is, you have a "master" backup, > which is always the most recent (one of the tweaks that I made was to > use systemimager instead of raw rsync to create that image). You then > use rsync to create hardlinks in such a way that only the changed files > take up additional space. For example, with a server that has about 5 > GB of space used up (it is a small machine), I can backup the four > hourly, four daily and four weekly snapshots in a total of about 10 GB > (instead of the 60 GB that would be required if every image were created > fresh each time). That also means that only the first image takes a > long time to create. After that, the other images are only the > differences between the current state and the most recent image.
rdiff-backup was *designed* to do this kind of incremental backup. Here's how I back up one of my partitions onto a removable USB hard drive: After mounting and such, rdiff-backup --exclude-other-filesystems --preserve-numerical-ids /farhome /usbackup/backup-by-rdiff/farhome It only copies what's changed, and it uses reverse differences (insteaf of hard links) to keep old versions alive, in case I ever need to see them again. -- hendrik -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
