On 11/17 11:13 , Les Mikesell wrote: > The remote rsync doesn't send the hash matching the backuppc naming > scheme, so it can't identify matches that aren't in the previous > tree for that host.
oh. I thought that the backuppc pool heirarchy was just based on the md5sum (or similar hash) of the file in question; and that the file on the remote end would naturally hash to the same value. > Even if it did, the hashing isn't perfect so > additional checks would be needed that a stock rsync at the other > end can't do. oh. my understanding was more imperfect than I thought. > It should be possible to merge in the incrementals > in the files that are checked, but currently only the last full > is used. it might be nice to have a tool to do this; but it's probably only useful in corner cases like mine; where an incremental has a *lot* more files than the last full. (Unless we wanted to fill all the old incremental backups, so that each new incremental is done against the last incremental, rather than the last full....hmmm... this is how the other rsync backup tools tend to work, since they don't make a distinction between full & incremental backups when using rsync). > I've gotten by pretty well by just starting a manual full > from the web interface before going home if I know there are big > changed on one of my remote hosts. that's how I normally do it... not always possible tho, when the blackout period starts sometime after I leave work. :) > > > And you can add the -C option to the ssh > > > command to save more. > > > > This option really should be mentioned in the notes in the config.pl file. > > For old machines with slow CPU and lots of bandwidth it might not be > > worthwhile; but for fast machines with slow links, it would be worth > > reminding us of it. :) > > For slow CPUs it might also be worth adding -c blowfish to get the > more processer-friendly encryption. I ran a few tests today, doing incremental backups against my workstation, with the -C option on or off, and the -o CompressionLevel=9, and the -c blowfish option in various combinations. At least for this backup, done with a fast link (100MBps) on a moderate machine (dual 550MHz Xeon), the difference seems to be lost in the statistical noise. I'll see what difference it makes when backing up my 80GB server over the T1... once I get all the data transferred. > Note that ssh also has a config file where you can specify > CompressionLevel from 1 to 9 (default is 6). See man ssh_config. > You could also enable compression there if you want it for every > host. thanks for the hint. I knew that option existed, but I never looked into it. The only time I do compression with ssh, is for remote X displays, where it improves responsiveness notably. Otherwise I tend to do it at a lower layer. -- Carl Soderstrom Systems Administrator Real-Time Enterprises www.real-time.com ------------------------------------------------------- This SF.Net email is sponsored by the JBoss Inc. Get Certified Today Register for a JBoss Training Course. Free Certification Exam for All Training Attendees Through End of 2005. For more info visit: http://ads.osdn.com/?ad_id=7628&alloc_id=16845&op=click _______________________________________________ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
