(this is actually response to Jules Agee's posting as well, but as en email cannot have multiple addressees...)
>I should also add the logs are not for rollback purposes, they're for >consistent recovery of the system to a known working state, IE to recover >from unclean shutdowns. I understand that the logs are just for recovery purposes, but I'm wondering if I could use them for, let's say, simulating a crash and let the system do a "consistent recovery" which actually is a rollback. I am not sure if this is possible. Even if it is not very gentleman-like, it is very much an option because the damage in case of a complete data loss would be quite severe. So, I noticed that there are some log (?) files in the db directory, named __db.001 to __db.005, one of which has 18 MB: -rw------- 1 cyrus mail 8192 2005-03-11 16:50 __db.001 -rw------- 1 cyrus mail 270336 2005-03-11 16:50 __db.002 -rw------- 1 cyrus mail 98304 2005-03-11 16:50 __db.003 -rw------- 1 cyrus mail 18563072 2005-03-11 16:50 __db.004 -rw------- 1 cyrus mail 32768 2005-03-11 16:50 __db.005 -rw------- 1 cyrus mail 211602 2005-04-05 04:56 log.0000000002 -rw------- 1 cyrus mail 4 2005-03-11 16:50 skipstamp Hm...I'm asking myself what the __db.004 would contain? 18 MB seem to be a little too much for just storing metadata - but could be, if the content of __db.XXX is never expunged but always appended. [...5 mins later...] I just took a look at the __db.004 file and it seems not promising at all, for the majority of the 18 MB it seems to contain only a sequence of approx. 70 bytes (mostly null values), repeated over and over again. So to me this seems to be the only weak, distant glimpse of hope: IF the _db.XXX files contain mail bodies in some compressed/internal representation, it could be possible to extract them from there, at least most of them. Could there be a way to extract to extract the mail bodies from the __db.XXX files (for example by forcing the system into an inconsistent state so that cyrus uses its binary checkpoint and archiving files to recover) - or are the mail bodies _really_ just stored in the individual files (which have been definitely deleted) as Jules Agee pointed out? What do you think - imagine you are allowed to do anything and not restricted to good manners or "clean" procedures. What else could I try? Alex --- Cyrus Home Page: http://asg.web.cmu.edu/cyrus Cyrus Wiki/FAQ: http://cyruswiki.andrew.cmu.edu List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html
