[Dovecot] Providing shared folders with multiple backend servers

[Stan Hoeppner]

On 1/8/2012 2:15 PM, Sven Hartge wrote:

> Wouldn't such a setup be the "Best of Both Worlds"? Having the main
> traffic going to local disks (being RDMs) and also being able to provide
> shared folders to every user who needs them without the need to move
> those users onto one server?

The only problems I can see at this time are:

1.  Some users will have much larger mailboxes than others.
    Each year ~1/4 of your student population rotates, so if you
    manually place existing mailboxes now based on current size
    you have no idea who the big users are in the next freshman
    class, or the next.  So you may have to do manual re-balancing
    of mailboxes, maybe frequently.

2.  If you lose a Dovecot VM guest due to image file or other
    corruption, or some other rare cause, you can't restart that guest,
    but will have to build a new image from a template.  This could
    cause either minor or significant downtime for ~1/4 of your mail
    users w/4 nodes.  This is likely rare enough it's not worth
    consideration.

3.  You will consume more SAN volumes and LUNs.  Most arrays have a
    fixed number of each.  May or may not be an issue.

-- 
Stan