Lately, I've been looking at Zimbra with interest, as we are wishing to move away from an ageing qmail/courier/vpopmail installation.
However, there is one thing that keeps nagging at me - Zimbra's hardware requirements. Whilst not "crazy", they do seem mildly high for what essentially is a mail server. While I understand it's a bit unreasonable to use this as an comparision, I'd like to note that that mail toaster setup is running a few thousand email addresses off PIIIs.
Zimbra also uses similar-ishy software - postfix, mysql, apache etc, and if I'm not mistaken, at the end of the day, all "Zimbra" is is an unified solution that ties together the various OSS applications, and adds a very polished webmail and admin interface.
Please don't get me wrong - I'm not trying to troll or anything, just a bit perplexed by the apparently high requirements that Zimbra requires, given what it does.
For what it's worth, the hardware we're looking to run this on is a Xen-ified AMD Opteron 170 2GHz with 2GB RAM (we will probably beef up the RAM if we decide to go with Zimbra). This is running RHEL4, with CentOS VMs. We have around 20-30 mail users.
Many thanks for any input you may have on this...
In addition, if we were to decide to transition to the paid Network Edition, am I right in thinking this would not be supported as long as Zimbra was running in a CentOS VM? i.e. only a full-on RHEL VM would be supported?