Multiple Send Connectors: same address space, different smart host and source servers

[whatwaht]

Hey all,

Some details first:
2 x Exchange 2013 CU 23 Servers in a DAG (both on Server 2012)
1 x Exchange 2019 CU 12 server (Server 2022)
1 current on-premise mail scanning server
1 new on-premise mail scanning server

The 2019 server is newly installed and am just testing.

We have one Send Connector configured thus:

• Smart Host IP is set to our current on-premise mail scanning server
• Address Space SMTP Domain *
• Source Server: the two 2013 servers
• Not scoped

Without breaking existing mail flow, can I add another Send Connector with:

• Smart Host IP set to the new mail scanning server
• The same Address Space of SMTP Domain *
• Source Server just the new 2019 Exchange Server

And with this will our users still connecting to 2013 use the old mail scanning server, while test PC's connecting to the new 2019 server use the new mail scanning server for outgoing mail?

thanks

jc

[#2 · Accepted solution]

There's a bit of black magic that goes on under the hood with internal message routing, and I don't believe you would get the results you are looking for (ie users still connecting to 2013 use the old mail scanning server, while test PC's connecting to the new 2019 server use the new mail scanning server for outgoing mail). If you want to be guarantee that only certain users use a send connector, I'd look at using transport rules to send mail from certain users to a specific connector.

[#3]

Thanks @Dan Snape you are right in what result I was looking for.

Dang it, I'll look at transport rules then, or as we aren't a 24/7 organisation maybe find a time to change some IP's (port forward on the firewall and Send Connector) and just test the new mail scanning server out of hours.

[#4]

Hi @whatwaht,

have a look at RouteBySender tool.

[#5]

All good thanks@Victor Ivanidze 

I picked a time, switched the send connector and tested sending, all good; changed port forward on firewall and tested receiving; all good.

Perks of not having a 24/7 business!