[LMStone]

Although we prefer SLES, there really is no one "ideal" Linux distro IMHO on which to run Zimbra.

If you want a commercially supported distro, then you can use SUSE, RH or an Ubuntu LTS.

If you want clustering, then you can only use RH.

In the past, Zimbra has done most of their dev work on RH as we understand it, but they do certify (and test) Zimbra on all the distros they list as "supported".

We like SUSE because of YaST, SuSEconfig scripts, and a number of other items that, to us, make system administration tasks easier than on RH and Ubuntu.

We also support Macs, but even a number of edus with whom we work who are primarily Mac shops tend to run Zimbra on Linux.

Hope that helps,
Mark