we have to migrate our internal mail server to another solution. Maybe mailEnable.
The internal mail server solution we are using at the moment covers following mail flow out of the box:
- The MX record of the domain points generally to the ISP.
- Some mailboxes are hosted by the ISP. They are always directly contacted from the mail clients (MSA).
- Some other mailboxes are also hosted by the ISP. But they are fetched by the internal mail server 1:1 by pop3 into their internal mailboxes. Mail clients (MSA) of these mailboxes always contact the internal mail server.
- Some other mailboxes do not exist externally (ISP), but they do exist internally and are fetched into their internal mailboxes from an external catch-all address of the domain.
- Does a matching internal distribution list (mail group) exist, the fetched mails from the external catch-all address are delivered to the internal lists which can contain internal and external mailboxes. See also last 2 points.
- One internal Mailbox fetches mails not only from one corresponding external mailbox but from multiple external accounts. One of these multiple accounts is the catch-all address of the domain.
- All incoming fetched mails are processed by the internal mail server through multiple global and per mailbox rules. With the aim of server-side sorting into subfolders, forwarding to other mailboxes etc.
- Users with external-only mailboxes always use the ISPs SMTP to send mails.
- Users with fetched-into-internal or internal-only mailboxes always use the internal mail servers SMTP.
- The internal mail server has a general SMTP route to always relay outgoing mails through the ISPs SMTP to avoid SPF problems...
- ... except communication between internal-only or fetched-into-internal mailboxes. These emails do of course never leave the house and are always delivered locally.
Is it possible to build this flow based on mailEnable? And which parts are out-of-the box, which parts need a mailEnable plugin and which a third party plugin?