On Thu, Dec 08, 2005 at 02:49:22PM +0100, Kern Sibbald wrote: > Bacula's Base project will accomplish something similar, but *much* > more secure from the stand point of making a false match.
[snip] Would you also consider allowing an option to do away with the requirement to explicitly specify the base backups? Or, alternatively, an option to make all backups be considered base back-ups? :) OS patches, application patches, and popular documents are moving targets, so I don't want to have to manually specify a base. Meanwhile, crypto hash algorithms such as SHA-1 typically have collision rates on the order of 1 in 2^69 (even with the recent weaknesses), and I only have a few million files, so I'm not too worried about accidental hashes. You're more likely to have a media error than a collision! But if you really want to be paranoid, maybe have an option to actually compare, byte by byte, the two files in question, either using the copy on tape or by asking the previous host to send it again? It would make your tape drives and/or your hosts more busy, but it would eliminate any possibility of a hash collision leading to lost data. > > > I've been using AMANDA for a while, particularly because it can > > > easily support bare-metal-recovery and it's free. > I haven't looked at AMANDA's bare metal recovery, but if someone > thinks it is easier to use than Bacula's, I would appreciate to hear > about it ... I wasn't comparing AMANDA to Bacula, since I don't know Bacula. But AMANDA bare-metal recoveries are easy. AMANDA is typically configured to use system native backup/restore tools on the backend -- dump/restore, tar, cpio, whatever. The tape has an AMANDA-specific header, but you can just mt fsf over it. So, you get AMANDA to print out a copy of that night's backup tape layout and dumplevels after making the backup, and you keep the last few sheets. Then, if you need to do a bare-metal recovery, you can just read through the sheets and figure out which tape files need to be restored (ie. latest level 0, then latest level 1 if more recent than level 0, etc.) Then mt fsf to the right entry on the tapes, and run restore, tar, or whatever to pull the data off. No AMANDA-specifics needed. Of course, since AMANDA uses the system native tools, it is limited by their capabilities. For example, if your OS native dump/restore doesn't support exclude lists, and you need exclude lists, you could have trouble. If you use tar instead, you're likely to run into tar limitations such as ACL support. And, of course, a "Base" or single instance storage setup would probably not fit in the design, either. I didn't even bother asking. Thanks, Russell, Kern, and Phil, for answering my questions! It's nice to see an active community. - Morty ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
