I've been trying to install the open source zcs on ubuntu 10.04 for the last few days...
I've actually been successful in this, however there is an existing mail server at our facility, and so make the zcs a sort of "drop in" for the network, it has the same ip address and hostname as the original mailserver.

I'm only able to put it online after the business closes (7pm) when I can take the old server off the network.

For the most part, the process works. (send mail, receive mail, access web interfaces from the real world, etc) but there are some things that I need to learn, odd behaviors that I need to track down, (error in admin console logins) and one complete mystery as to why the logger isn't functioning.

so, here's my plan, perhaps someone else has encountered similar, or can give any feedback.

- create DNS records at our isp for a new box - say "zcs.mydomain.com"
- DNS will still point to our firewall xxx.xxx.xxx.xxx
- Firewall will perform NAT to our internal network 10.0.0.x
- Create new rules to forward ports to the new zcs
- re-install zcs with unique hostname on our network
- give zcs a non-used internal ip address on our network 10.0.0.x

after installing this, I should have connectivity to download updates, signatures, ssh into the box, etc., without having to take down the original mail server.

Q: after this install, I should be able to send mail back and forth to the users I create on zcs.mydomain.com - correct? (to test mail functionality)
i.e. - log into the mail server web interface at https://10.0.0.x

if the odd behaviors occur again, I can ssh in and try to find the info for posting into a forum post...

Second half

once it seems to be up and functioning well, I intend to change
public DNS MX records to show that "zcs.mydomain.com" is now the
mail exchanger for that domain...
-A records still point to the wan ip of my firewall...
-change the firewall port forwarding for smtp, https, to the zcs internal ip address instead of the old mail server...

Does this sound correct? or am I missing something obvious here?

what I've learned through trial and error is that it seems that the zcs needs to be live on the network for the install to go smoothly
(I've tried it once without it being on the LAN, had MANY problems)

In a nutshell I need to re-install zcs, live on the network, and not have to remove an existing mail server from the network...