Hey,

I have customer with special requirements. Customer runs their Exchange 2013 hosting hundreds of mailboxes with different domains. They need to pass particular emails to secure remote SMTP gateway. The connections to gateway must be forced via TLS.

The remote SMTP gateway accepts email only to specific remote domains.

For example:

1. If customer sends email to @gmail.com or @outlook.com the email should be routed via MX records to appropriate remote SMTP servers.

2. If customer sends email to one of domains handled by secure remote SMTP gateway, is should be routed to that gateway. Gateway can provide a domain list (updated daily) which it allows to relay. So let say if customer sends email from @domainA.com to @RemoteDomainB.com listed in the list, it should go through secure remote SMTP gateway.

As mentioned, secure remote STMP gateway provides .txt file with domains.

Can this be accomplished within Exchange 2013?

How this "send connector" could be configured with specific remote domain list, and updated daily?

Any ideas?

T

There is no source-based routing like that in on-prem Exchange 2013

You can use 3rd party software such as:

http://ivasoft.com/routebysender2013.shtml

or use EOP/Office 365 as your SMTP gateway and you can use criteria-based routing.

As far as updating, you can script that with powershell as a scheduled task I would im