Need some advice

[Rob Siemborski]

On Fri, 18 Jul 2003, John C. Amodeo wrote:

> I am looking for some sound advice for the following situation I'm
> currently faced with, and I was hoping someone has some good advice to
> give me...

I'll let Ken answer the virtual domain parts, but I'll try to point you in
the right direction on some other things.

> We want this new Cyrus installation to run on an HA cluster, but for all
> intents and purposes, we are looking to combine these 15 'virtual'
> servers into 1 Cyrus server with virtual domain support.

You'll want to think very carefully about how your cluster is designed if
you're going to be sure to be consistant under all workloads.

> One of the biggest roadblocks I've come across so far is the LDAP
> authentication.  From what I understand, LDAP information is no longer
> stored in the imapd.conf file.  If this is the case, I would need to
> point SASL at the root of the LDAP server, which would create an
> obstacle for duplicate usernames in the organization's directory
> structure.  I am not sure if renaming user's username is a feasible
> option at this time, but if necessary, we would be able to individualize
> the usernames with some effort.

The LDAP config is placed in saslauthd.conf, Its pretty flexible and
I'm sure it should do what you need.

> Lastly, it would seem to me the process is messy to merge the
> mailboxes.db files from 15 Cyrus servers to 1 Cyrus server if I were to
> copy all the data into the new mailstore, run reconstruct, etc... which
> I would rather not do.  I'm toying around with the idea of setting up
> some sort of IMAP Proxy, so I can install the new servers in parallel
> and move user's mailboxes randomly with very little downtime.  Does
> anyone have any experience with a setup like this?  Are my ideas to
> grand given the limitations of my current setup?

This seems to be an ideal application of the Cyrus Murder, where you have
many backends and a single frontend (even if it does feel a bit
heavyweight for what you're looking to do).

You'd sort of go in reverse of the normal setup, moving from many backends
to one, instead of from one to many, but there's no reason this can't be
done, really..

Once you got down to a single backend, you just remove the frontend and
mupdate server from the system and you have your single machine.

This is only if you want to do the upgrades over a long period of time of
course, if you want to do the upgrade overnight, its probably better to
just transfer the data using an IMAP client (like UW's mailutil).

-Rob

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Rob Siemborski * Andrew Systems Group * Cyert Hall 207 * 412-268-7456
Research Systems Programmer * /usr/contributed Gatekeeper