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<div><br>> It looks like partimage works on the device, rather than on a mounted<br>> filesystem. The potential problem would be you're reading bits from<br>> the disk as other things are being overwritten.<br>> </div><div> <br>> Lets say you have bigfile.zip, and you start the backup. partimage<br>> sees bigfile.zip takes up 40MB, and starts reading it. While it is<br>> being read, bigfile.zip is updated, and is now 45MB. What happens is<br>> undefined:<br>> <br>> 1. If your zip software built a new bigfile.zip, then renamed it over<br>> the original, then you'd possibly get the old copy of bigfile.zip<br>> 2. If your zip software actually mucked about with bigfile.zip<br>> in-place, you might get a corrupted file in your backup<br>> <br>> Even in case #1, once the original bigfile.zip file is "gone", it's<br>> space could be overwritten (ex: by a transaction log indicating the<br>> new bigfile.zip contents), thus again causing corrupted data.<br>> </div><div><font color="#548dd4">Wouldn't this happen also by my current method using dd ?</font></div><div><br>> Generally, when you're backing up data at the device level, you want<br>> to guarantee nothing else is changing that data at the same time. It<br>> can be overwritten because it *might* be okay (/usr/local should not<br>> change during your backup window, for example), but that is really<br>> your call to make.<br>> <br>> The easiest solution to this problem would be LVM. You can snapshot<br>> the logical volume, fsck the snapshot, cleanly back it up, and remove<br>> the snapshot. You can guarantee the backup is as the disk was at one<br>> point, rather than a moving target over time.<br>> </div><div><font color="#548dd4">I will look into this.. Is it hard to set up on a running system?</font></div><div><br>> As an aside, partimage doesn't appear to support ext4. Just FYI if<br>> you're building new systems.<br>> <br>> --<br>> Chris Irwin<br>> <chris@chrisirwin.ca><br>> <br>> _______________________________________________<br>> kwlug-disc mailing list<br>> kwlug-disc@kwlug.org<br>> http://kwlug.org/mailman/listinfo/kwlug-disc_kwlug.org<br></div> </div></body>
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