Just this past week, I put in a G5 running Tiger Server and Kerio MailServer at a client, with about 50 users. We migrated them from Windows SBS 2003. Kerio makes a connector so you can use Outlook on Windows clients and it looks and behaves virtually the same as when connecting to Exchange. They also have an Exchange Migration Utility that did a pretty good job of pulling the Exchange mailboxes over. The utility is still a beta and I did run into a few issues with it, but by and large the migration was a smashing success. KMS also works very well with the Exchange connectivity in Entourage 2004SP2. Tip: If you run Tiger Server on the same machine as KMS, Kerio’s LDAP service won’t run on the default port (389)– change it to use 3268, which is the default port for Microsoft’s Global Catalog Service (and the default LDAP port set in Entourage Exchange accounts), and that’s one less thing you’ll have to configure in Entourage.

We set the client up on Open Directory, and it works great. You tell KMS to add a user, it asks you if you want to add one that’s ‘internal’ to Kerio or an account that already exists in Open Directory. If you choose Open Directory, it gives you a list of the users you can add, and boom, that’s it. They have an e-mail account. When they change their OD password, so changes the mail password. You can also publish their name into Kerio’s equivalent of the Exchange Global Address list with a couple extra mouse clicks.

The webmail is gorgeous, and works equally well on Macs and Windows– it puts Outlook Web Access to shame. It also has WAP functionality, and works to a degree with Blackberry handhelds (though admittedly nowhere near as well as Exchange with Blackberry Enterprise Server).

One thing I do not like about it is the decidedly inconsistent administration. Some things have to be set up in the webmail, some things in the admin utility, etc. It’s kind of all over the place that way. You also cannot add external users to a distribution group, which is a pain in the butt. Some user settings that I would like to be able to apply globally can’t be applied that way, it’s per-user only. But all in all, it is a good product.

If you’re considering rolling this out somewhere, I highly recommend setting it up on a test machine with (if possible) an external IP and possibly a ‘throwaway’ domain name, so you can actually use it as a mailserver and test out configuration scenarios. Put it through its paces as much as you can during your 30-day demo– you’ll be glad for the experience later when you set things up for real. We even built an SBS box in my office and populated it with dummy data to test the Exchange migration.

~Philly