Murder cluster questions

[Ken Murchison]

Brenden Conte wrote:
> I have some questions, mainly around murder and versions.
> We're looking to expand to a Murder cluster, but are still running 2.2 
> versions of the software.  Obviously, i would like to use the latest 
> version for any new installs, so I was wondering - both in the context 
> of building the cluster as well as future upgrades - if there is a 'all 
> same version' requirement (i.e. all servers must be upgraded at the same 
> time) or whether the protocol was standard enough that it didn't matter 
> (Between frontend and backends?  Between backends (i.e. moving a 
> mailbox)? Master vs frontend vs backend?)
> Naturally, this question doesn't involve using "new" features not 
> present in the older versions.

I don't believe that any changes to the MUPDATE protocol have been made 
between 2.2 and 2.3, so upgrading single components *shouldn't* be a 
problem.  However, given that the cyrus.index and cyrus.cache files 
contain additional info in 2.3, I probably wouldn't move mailboxes from 
2.3 backends to 2.2 backends.  Note that we haven't done a migration 
such as this at CMU (yet) so what I've said is purely an educated guess. 
  I haven't spent a lot of time thinking through all of the particulars.

-- 
Kenneth Murchison
Project Cyrus Developer/Maintainer
Carnegie Mellon University