[CentOS] Re: Mail server setup for small ISP

Matt wrote:

...

   I will probably have to design an e-mail (and other components)

infrastructure for a small ISP soon (WISP).

   I'm doing some research to determine which components would be best to

offer e-mail services to their client and allow the staff to manage accounts easily.

   I usually use virtual machines a lot for isolation and easy backups and

migration (when a hardware node is underpowered, it is easy to migrate one or more virtual machines to another hardware node easily).

   I have looked at iSCSI and drbd for high-availability of the storage:

http://www.pcpro.co.uk/realworld/82284/san-on-the-cheap/page1.html.

This looks like it should be doing a great job of high availability storage.

   For mail server, I guess I should look at an MTA and IMAP/POP server

that supports LDAP and/or MySQL for users. Postfix should be a good choice for MTA, as I know it (at least a little, but I know sendmail better). For IMAP/POP, I'm not sure... Would dovecot be sufficient, or should I try cyrus. I'd rather use components that are available for base or extras repository (or rpmforge). I think that squirrelmail and horde would do a good job for webmail.

   There shoudn't be any troubles having some redundancy for DNS, web

servers, mtas, but what about IMAP/POP? linux-HA? MySQL replication should be enough, I guess. Or maybe linux-HA as well. I wonder if I should add GFS to the mix to have multiple IMAP/POP servers use the same storage. Or maybe IMAP proxies?

   Any insights welcome :).

www.directadmin.com

Been running it on CentOS for years. Added Clamav and spamassassin to it. It utilizes Exim and dovecot along with standard bind and apache stuff. You pay monthly or yearly license fee. Its pretty cheap really. You can also pay a one time fee for a given machine.

Thanks

Does it offer some kind of high availability features? Does it provides an API (for account creation/management from another system)?