On Mon, Jul 24, 2006 at 04:42:10PM +0200, Christian Borntraeger wrote: > On Monday 24 July 2006 16:06, Dominic Coulombe wrote: > > in *theory* you can do live backup of machines with journaled filesystems > > (at least ext3) without any problem. > > Linux will repair filesystems from journal after recovering your backups. > No, that does not work, because the journal is backed up as well. The journal > on the backup might be several minutes older that the real journal of the > file system. So the journal replay might even destroy the file system because > it does not reflect the current state of the disk in any way.
Don't forget, also, that the filesystem is a moving target: if you do not stop all activity to it during the backup, then you are almost guaranteed to have blocks on the backup that have been updated *and committed* after they were backed up, and so will not be reconstructed during a log replay. I'll echo the comments of everyone else: Backing up a live filesystem from outside Linux is playing with fire. YOu might get away with it, but you *will* eventually get burned. -- Jay Maynard, K5ZC http://www.conmicro.cx http://jmaynard.livejournal.com http://www.tronguy.net http://www.hercules-390.org (Yes, that's me!) Buy Hercules stuff at http://www.cafepress.com/hercules-390 ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
