I wasted too much time this afternoon trying to figure out why rdiff-backup failed on ONE backup job in the wee hours of Sunday morning. All the others had completed successfully as expected. I finally Googled it. Guess what? It’s a known problem with daylight savings time. The full explanation is here: http://wiki.rdiff-backup.org/wiki/index.php/NoMetaData.
Here’s the error message that showed up in our logs:
Previous backup seems to have failed, regressing destination now. Warning, could not find mirror_metadata file. Metadata will be read from filesystem instead. Fatal Error: No metadata for time Sun Mar 11 03:00:19 2012 (1331449219) found, cannot regress Fatal Error: Lost connection to the remote system
In theory, removing the older of the two current_mirror.* files will fix the problem and rerunning rdiff-backup. I think I managed to botch it and eventually ended up removing most of the older backups in the process. *sigh* At least we only took out the mail backup and most of our users download their mail to their home directories anyway. Everything’s running again now.