Lots of different ideas came in regarding how to address the issues of
setting up a sendmail cluster. Add to that 12 messages and 4 phone calls
from people wanting to know what I found out so they can implement it :-)
Suggestions ranged among:
A) Forget the cluster and get a really big box
B) Use qmail, which has a different file mechanism and gets
around a lot of the NSF problems that sendmail encounters.
C) Have all machines in the cluster forward incoming mail to one
machine so that only one is responsible for locking the
inboxes.
D) Use a NetApp.
My current thinking is to go with a low end netapp (
http://www.netapp.com)
which has a slighly better implementation of NSF and has the benefit of
being fully scalable. I'll add to this setup a Cisco LocalDirector which
will do load balancing, and redirect people to another machine if the main
machine is down. Instead of 3 Alphas, we'll go with two. We'll then NSF
the mailboxes off the netapp (and maybe even use the netapp to
load-balance our two web servers).
A couple people did ask why we needed so many mail machines, especially
when a single 533 would be easily able to handle 20,000 accounts. The
primary reason is scalability. We're adding on average 50 new email
accounts a day (and deleting about 4). We very quickly expect to exceed
resources so want something that can scale upward with minimal work. The
netapp/localdirector solution also provides for redundancy and for
continued uptime if we were to take one of the servers out of action for
service.
At this time, I don't have pricing on a netapp, but their vendor will be
paying a sales call Monday afternoon. The Cisco LocalDirector looks like
it has a retail price of about $15,500, but we get a good reseller's
discount so it looks much more attactive for us.
=-=-=-=-=-=
Robert Hayden rhayden_at_means.net UIN: 3937211
IP Network Administrator
http://rhayden.means.net
MEANS Telcom (612) 230-4416
Received on Fri Apr 10 1998 - 14:31:35 NZST