Clustering and replication

[Janne Peltonen]

Hi!

As a part of our clustering Cyrus system, we are considering using
replication to prevent a catastrophe in case the volume used by the
cluster gets corrupted. (We'll have n nodes each accessing the same GFS,
and yes, it can be done, see previous threads on the subject.)

Now the workings of the replication code aren't completely clear to me.
It can do things like collapse multiple mailbox changes into one and so
on. But is it in some way dependent on there being just one cyrus-master
controlled group of imapd processes to ensure that all changes to the
spool (and meta) get replicated? Or does the replication code infer the
synchronization commands from changes it sees on the spool, independent
of the ongoing imap connections? That is, do I have to have n replica
nodes, one for each cluster node? Or don't I?

Thanks for any answers.


--Janne Peltonen
Email admin
Univ. of Helsinki