I'm trying to figure out how to setup the network to serve multiple organization e-mail server through the same WAN IP.
It can be done with a multi organization e-mail server, but is there a way to set it up using multiple, single organization, e-mail servers?
The only way I can conceive, is through port translation in the port forwarding on the router, e.g.:
IMAP service of the e-mail server1 (mail.domain1.com) is offered on port 25000
SMTP service of the e-mail server1 (mail.domain1.com) is offered on port 35000
IMAP service of the e-mail server2 (mail.domain2.com) is offered on port 25001
SMTP service of the e-mail server2 (mail.domain2.com) is offered on port 35001
IMAP service of the e-mail server3 (mail.domain3.com) is offered on port 25002
SMTP service of the e-mail server3 (mail.domain3.com) is offered on port 35002
Is there a better solution?
What I would like to accomplish is to find an easy solution, to serve multiple e-mail domains inside a single company, with an unique WAN IP.
I could opt for a multi organization e-mail server, like Zimbra, Zarafa, but I would like to continue to use Zentyal, Nethserver solutions, without delving too much into new e-mail server solutions.
Now I'm doing a lot of experimentation, before to accomplish this in production environments, trying to find the best, and easier, solutions based on my skills and needs.
Both Zentyal and Nethserver, can be adapted to serve this purpose, but they are conceived for a single organization: each e-mail address is associated to an user of the same local domain, so I need to use alias and similar. Making the whole thing a mess.
Usually, my customers use max 2 or 3 e-mail domains, so would be very easy to use 2 or 3 VMs, each one serving e-mail for a domain. And, moreover, very often it happens that my customers ask me to use an additional e-mail domain, after many years using just one. It would be easier for me, just to add a VM with another e-mail server instance, instead to change the e-mail server from ground up, so needing to migrate all the existent e-mails...
A solution would be just start to use a multi organization capable e-mail server since the beginning, so to be abble to add a domain when needed.
Just trying to understand if there is a way to continue to use the existent e-mail server, just adding a new one. 99% of times, everything resides inside an virtualization server, so would be very easy, just to add a new e-mail server.
Thank you for the suggestions, of course the lack of knowledge about the subject, is the culprit