Doing Cyrus *right* for a large installation

[Andrew Morgan]

On Thu, 15 Jan 2009, Simon Matter wrote:

>> But then I started thinking about how I was going to backup all this new
>> data...  Our backup administrator isn't too excited about trying to backup
>> 12TB of email data.
>>
>> What if we used Cyrus replication in combination with delayed expunge as a
>> form of "backup"?  We currently only keep 1 month of daily backups
>> anyways...
>>
>> For those of you running large installations, how do you back them up?
>
> I don't have a really large installation anymore but what I still do is:
> 1) use 'expunge_mode: delayed' and 'delete_mode: delayed' (a nice side
> effect is increase of performance on certain operations). (expunge/delete
> period is 7 days in our case)
> 2) use rsnapshot to replicate all cyrus data to a separate storage and
> maintain some history while still saving space. (daily in our case)
> 3) create offsite backup of the rsnapshot storage. (weekly in our case)
>
> That's our poor mans solution we use here, and it is very KISS. Other
> ideas may include using advanced filesystems like ZFS or build something
> around DRBD, maybe all in combination with deduplication (something like
> using a Datadomain box instead of rsnapshot).
>
> I'm also interested to hear what others do.

rsnapshot, neat!  I haven't seen that until now.  If I'm reading this 
right, rsnapshot works like ZFS snapshots, where the only "extra" data in 
each snapshot is the data that has changed?

This kinda goes back to a discussion last week about filesystems.  I think 
I would like ZFS, but I'm not sure I want to switch our Cyrus stuff over 
to Solaris.  We run a fair amount of Solaris on SPARC here, but no Solaris 
x86.  Unfortunately the SPARC hardware is not as cheap as x86.

I was pondering using delayed expunge and delayed delete with a 30 day 
period, and just replicating (Cyrus replication) to another data center.

Hmm, I should try to figure out how much overhead it would be to keep 30 
days of delayed expunge/delete...

 	Andy