Murder cluster questions

[Patrick H Radtke]

>> 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.

We've run a murder with 2.3 backends, 2.2 frontends and used both 2.3 and 
2.2 (at different times) for the murder master with out problems. We've 
made no attempt at running a mix of backend versions, though as Ken 
mentioned it shouldn't be a problem as long as you don't transfer 
mailboxes.

-Patrick