Doing Cyrus *right* for a large installation

[Simon Matter]

> 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.

Regards,
Simon