This is not related to SME server at all.
We have a large WAN that utilizes around 7 domains and subdomains (say main.domain.gr and area1.main.domain.gr to area6.main.domain.gr). Each one of the above has its own MX relay and mail server (FYI, one of the areaX.main.domain.gr is hosted on a SME Server 9.x, but that is not related to our story here). Highest load is exhibited on the central main.domain.gr.
There is also a web app that generates a lot of mail traffic that includes attachments. This web app network-wise is close to the main.domain.gr mail server and, for that purpose, used the latter to send (large) mails recipients on any one of these 7 domains.
This process strains a lot the main.domain.gr mail server. What would you propose to ease the load on this system?
My idea was to implement an SMTP server and send messages from the web app there, instead of the main.domain.gr server. Messages sent from this server should show to be originating from a specific @main.domain.gr mailbox (the one of the web app). This new server would not receive (if possible) any mail, there would not be any MX records for it (apart from any SPF ip4 records to mark messages sent as valid ones for the main.domain.gr domain)
1) Does this sound like a nice idea? We do have the resources to host another server of course
2) What would you use to perform this task? Any solid solutions?
Thanks in advance for any info provided.