We are new to Zimbra and email hosting in general, though we have a good understanding of the OS and the general terms defining the technology. In our current corporate environment we are trying to build a ZCS5.011 server to manage several existing email domains locally. These domains all reside with our current ISP, including name servers, MX and A records.
Our ZCS server has one public IP number sourced from our NEW ISP, run through SmoothWall, and through a horizon DNS setup a single internal IP number that we assigned. Zimbra Proxy Server (IMAP/POP Proxy) has not been installed. All the existing email domains reside with the current and soon to be OLD ISP.
We have started our testing of the ZCS server by setting up one domain - mail.domain.co.za - asked of us when the server is installed, and two ZCS domains that include virtual hosts as well, mail.domain2.co.za and mail.domain3.com. Only the latter two domains have their A and MX records amended now to point to our ZCS Server public IP number. The first or former domain name has not yet been moved, as it too is originally hosted by the soon-to-be-old ISP, but we are not testing that domain as yet, and therefore we only use it to authenticate web users of the ZCS Server.
When we test this setup we find the following results happen:
1. Timeouts on public email domains used to send emails to from the two test ZCS domains.
2. Intermittant POP reception to these two test ZCS domains.
What we are wanting is some assistance in a diagram of sorts that better explains the correct flow of traffic between MX, A, and name servers, and the local ZCS server, and that someone can help explain to us in terms of our scenario as explained above?
Also, it would be good to understand, having people access this ZCS server using Thunderbird and Outlook, whether we should be running Proxy as well?
Please let us know of posting copies if certain log entries would help.