On Mon, 24 Jan 2000, Brian Baquiran wrote:
> Hi,
> I posted a question a while back about building large mail systems using an NFS
> server and a lot of smaller SMTP/POP3 machines mounting the NFS-exported
> maildirs. While we may well end up setting up something like this, I'm worried
> about the NFS server being a single-point-of-failure.
> What are the alternatives to this architecture? I think someone else mentioned a
> farm of lighter-weight servers without NFS. How would this work? How would users
> know where to get their mail?
One thing I am looking at currently is a RAID mounted and available for
several machines. Nexsan has such a box. The Nexsan box is connected to
each of the mailservers SCSI buses. This is kinda a cheap SAN solution as
far as I know.
My plan, although not using qmail this time (because of specific needs),
is to have several mailservers in front, acting as primary and secondary
MX (with additional offsite machines also working as secondary). When one
of these machines fail, they will still be able to access a common spool,
without using any form of networked filesystem. According to Nexsan, you
should be able to give the machines priorties for access.
The downside is the cost. I could get 4 mailservers for the prize of
the Nexsan box.
Any opions on this solution? One I would expect is that the Nexsan is a
single point of failure, and well, it is. Even though it is planned to
have RAID-5, with an extra disc available at all time. If the RAID box
fails, it's down. I would then like to shut down the SMTP receivers so
that it get queued remotly, but that could be a problem.
--
Thorkild Stray
