[Dovecot] 1 week after full migration to 1.1v

[Ed W]

Raphael Bittencourt S. Costa wrote:
> And backup is a problem here, so an security filesystem is very 
> important for not losing mail.


I have been using rsync (rsnapback) for many of my backups, but it 
struggles when you point it at hundreds of thousands of files in a 
directory.  I have seen a number of solutions involving running multiple 
independent rsyncs for each maildir to keep the file numbers reasonable, 
but it's a bit of a fiddle

More recently I was reading webmail.us / rackspace's notes on their 
backup strategy and they have  presentation on their use of S3 which is 
kind of cool.  Reading between the lines they use something like an MD5 
hash of all their files and then copy the files up to remote storage 
(S3) based on the file hash name.  They then use some kind of index to 
record who has which files and which maildirs they belong in.  Seems 
fairly cheap to make incremental backups and robust to maildirs tendency 
to move thousands of files from new/ to cur/... 

There is an implementation of a similar algorithm via "brackup" - it 
might be interesting for your needs?  I plan to do some more 
investigation into it for backing up our maildirs
http://search.cpan.org/~bradfitz/Brackup/

Regards

Ed W