We are in desperate need of a new e-mail server solution and would
like to get opinions and real world benchmarks of what others are
using.
Here is our current setup and problems:
New Intel Xeon Xserve 4GB RAM, OS X Server (was 10.4.10 now 10.5)
using OSXS built-in mail, mail store is on connected Xserve RAID
(RAID 5).
There are 650 active mail accounts, with anywhere from 200-350
users being connected at once, (at least trying).
All accounts are IMAP.
We have set up Shared folders, also.
Users do not have mail quotas.
All users are in Open Directory. The mail server is also a replica
of the OD.
The problem we are having is the server can not handle this load.
We have worked for months with Apple and have not been able to make
things better. At peak times the server comes to a crawl, so much
so that mail connections time out etc.
So here is what we need:
Software that will run on an Intel Xserve/OS X server.
A solution that will do IMAP.
Can handle up to 400 users connected (which could possibly mean
thousands of IMAP connections).
The ability to do Shared/Public folders.
Integrate with Apple's Open Directory, either for authentication or
complete integration.
Some ability to migrate mail/messages from current system to new
system.
Since we've been dealing with this major problem since the middle
of August we really are ready to move on to another solution.
Are you running SpamAssassin and ClamAV on the same machine as you're
using for your IMAP users?
A single XServe should handle just the IMAP load you describe unless
you have lots of shared folders. And you can split the load you know
even if you are.
That is this is a solvable problem with OS X Server if done right.
-dhan
------------------------------------------------------------------------
Dan Shoop
Computer Scientist
iWiring / U.S. Technical Services
