Putting main website and mail on seperate servers using single domain

[apinto]

I'm probably not the best guy to help you as I've never done it.
However you will need for sure a few steps:
- Point your nameservers to Sentora (or any other DNS service oyu are using).
- On the DNS setup, add the subdomain as a A Record and insert the Linux IP (this will be the mail server, right?)
- Set the MX Records for the main domain to use the Linux Server.

Now the part that I'm not sure, but I would do this:
- Install Sentora normally on the Linux server.
- Find a way to replicate the accounts:
--- One way to do this would be using MySQL Replication (https://www.digitalocean.com/community/t...n-in-mysql)
--- Probably you will need to call the Sentora Daemon using some kind of hook (take care for security here as if you implement this insecurely you can give access to your server); make the Windows Server tell the Linux server Daemon to do the same action, this way you would have the same email accounts on Linux and Windows (so users can add and remove email accounts on windows and they will be updated on the real mail server).

Please keep in mind this is just theory, was not tested and needs developing custom code.

Hope this helped you