Best recommendations for e-mail serving infrastructure?

Question

Looking to find out infrastructure recommendations/hardware solutions/appliance solutions that can handle a fairly high volume of e-mail accounts and traffic.

There is a lot of cruft out there and marketing speak for hardware that looks way overpriced for what you get and at the same time there might be some great deals out there.

Quick spec. We have a need for hosting over 1500 domains and 8000 individual e-mail accounts (each with an average 3 aliases) and need to handle the POP/IMAP and SMTP. We also want to have some fairly advanced spam filtering and handling built into the inf. On average e-mail space usage doesn't go above 250mb. But some accounts will use 2-3GB.

We have our own datacenter and such, and up until recently have been using a third party hosting solution that tends to go down a lot lately and we are wanting to bring this "in-house" now. Just looking to see if there are any good directions I could be pointed for positive results you've had with e-mail solutions.

Answer 1

May I suggest you look into Zimbra Collaboration Suite. They just released their 6.0 server. Supports IMAP/POP3 and they have a great web based client. Also spam filtering is included. They have a FOSS and paid (Network Edition) versions availible. I have used both free and paid with great success. Zimbra stores the mail information in MySQL for fast mail experience and quick searching. I have mailboxes over 10GB with no performance issues. Its scalable with multiple server roles.

Answer 2

The only commercial email server that I know is scalable enough is CommuniGate from Stalker software. Lots of clustering and management features. Rock solid and great performance. I've used it for more than 10 years for a couple of clients while growing more than 10 times the original size with only two hardware migrations.

Or, if you have a really good technical team, do as most ISPs and use Postfix