On Tue, 01 Jul 2014 00:52:56 +0200 Jiri Bourek <bou...@thinline.cz> wrote:
> On 1.7.2014 00:28, deoren wrote: > > I'm still pretty new to running a mail server, but one thing I've > > come to appreciate over the years is a good backup strategy. Since > > I have always run my own servers for practice and for personal use > > I don't have access to Enterprise backup solutions. Because of that > > I usually just fall back to scripts and tarballs and offload the > > content on a regular basis. > > > > Right now I'm using LVM snapshots + tarballs for daily backups, but > > I'd like to get better coverage for incremental changes that occur > > throughout the day. The size of existing content is low, but (small) > > changes are frequent. > > > > I went with Maildir format because based on my reading it is > > referred to as time tested and corruption resistant. Because > > individual emails are stored as separate files this also leads me > > to believe that a version control system (Git, SVN) would allow for > > easy point in time restores. > > > > I'm also going to research the GNU tar utility's support for > > incremental archives as that sounds promising. > > > > Suggestions and warnings are most welcome. > > > > Thanks! > > Since you're using maildir, you might want to check rsync out as > well, especially with --link-dest. In short, you call rsync on your > backup machine like this: > > rsync --link-dest=previous-backup-dir source new-backup-dir > > This compares current files with their copies in previous backup. All > files which didn't change are hardlinked, saving storage space. This is pretty much what I do. I have a backup server that rsync pulls off the Dovecot Maildir on my desktop. With a backup server, most of the processing is done on the backup server: the box with the Maildir is only being read. For reasons I've long since forgotten, in order to keep hardlink increments to old backups, I use a separate cp -al on the backup server instead of doing --link-dest=previous-backup-dir. Theoretically, I should shut off the fetchmail that feeds my Maildir before doing such a backup (and probably shut down Dovecot too). But I'm the only user, so... A few days ago I deleted my whole INBOX and rsync'ed it back in a matter of minutes. Here's some info on my backup system: http://troubleshooters.com/lpm/200609/200609.htm If anyone's interested in backing up to Blu-Ray, here's some info I wrote: http://www.troubleshooters.com/linux/blu-ray-backup.htm SteveT Steve Litt * http://www.troubleshooters.com/ Troubleshooting Training * Human Performance
