High Availability for SMTP Relay Server

cosy M 6 Reputation points

Hi Folks,

Recently we did a migration from On-Premises Hybrid Exchange 2010 to Exchange 2016. All the devices and applications relay are being done through Exchange 2016 .
Now I need to patch this server with no downtime?

Currently, all the devices and applications are pointing to smtp.mydomain.com ---> Load balancer--->exchange 2016

So if I set up a new IIS SMTP and add it to the load balancer pool, will that route?


Exchange Server Management
Exchange Server Management
Exchange Server: A family of Microsoft client/server messaging and collaboration software.Management: The act or process of organizing, handling, directing or controlling something.
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  1. Kael Yao-MSFT 26,391 Reputation points Microsoft Vendor

    Hi, Cos.

    You may need to add the ip address of your new IIS SMTP relay server to the custom receive connector used for SMTP relay on your Exchange server.
    Otherwise, the receive connector won't accepts messages from the new server.

    Here is the Microsoft document on this topic for your reference: Allow anonymous relay on Exchange servers


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