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Jonathan Roberts wrote: >> Hope this helps > > Thanks for all the suggestions everyone. I think rdiff-backup seems > like a pretty good solution, though I wish it had some way to preview > files before deciding which one to backup. In this regard, I think OS > X time machine is the closest to what would suit best, but then that's > crippled by being OS X only and not being able to do backups across a > network. Looks like it is crippled by poor underlying technology. You have various approaches to emulate Time Machine with free (as in freedom) software. rsnapshot rsnapshot seems to try it via the hard links approach, this is good for disk IO, but looks messy to me. This is basically what Time machine does by the looks of it, although I struggled to find a proper explanation of Time Machine internals written by someone who knows. lvm2 snapshots Alternatively you could use LVM with your backup drive and use the LVM snapshot utility to make hourly snapshots of the backup volume, then just rsync files you want backed up to that volume. A little script to keep the LVM snapshots mounted (read only) would be easy to write. This is probably the best approach short of jumping to Open Solaris. The Solaris marketing is rather down on Linux LVM solutions, with several factual errors. I guess this is the advantage of having evangelists like Roman paid to convert you to their free software. I'll write a document doing the how and why if someone pays me, I might even make a marketing video if they pay enough ;) I've been meaning to document how to do this, since I saw the cock-up that is Windows 2003 "Volume Shadow Copy", which is just yuk. Open Solaris Either abandon Linux, or run Open Solaris on your back-up server, rsync the files you want to a ZFS volume, and use Time Slider. This gives you a proper solid implementation of Time Machine like functionality, but done the right way, with a GNOME GUI. http://channelsun.sun.com/video/opensolaris+demo+time+slider+in+opensolaris+2008.11/2972356001 There are some gains over LVM2, but it isn't as much as you might think if you check the current LVM documentation before believing everything one is told. LVM2 is a flexible beast. Insane Option Since the Open Solaris version works because Open Solaris has ZFS, you could see if you can do something like Time Slider with ZFS-fuse, there are script around from folk who used ZFS before Time Slider was released. This is unlikely to work yet - hence it being the insane option. Note that these kind of time machine like backups aren't really a substitute for a proper backup. Since they nearly all introduce a lot of complexity that a simple "tar", or "rsync" command wouldn't introduce. Also most snapshot technology needs attention if used with databases, since most databases need some sort of quiescence command run when making a hot backup (I wonder if sqlite is affected with Mozilla history files and such like?). There is a lot of discussion of Linux LVM with MySQL that covers the kind of issues, but some of the solutions are not things to bet the bank on. Most folks I know used early LVM snapshot in Unix to create a read-only copy of the database server volumes, so that a consistent version could be backed up to tape whilst allowing the database to be restarted. This model should inform your backup design decisions - on the other hand it may be for the average desktop that syncing to an external disk (local), and maybe an occasional backup to a remote place is good enough. -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/linux_adm/list-faq.html