Exchange 2016 using wrong network interface

Luke Kenny 21 Reputation points
2022-05-31T02:48:08.747+00:00

I have Exchange 2016 running in a VM. It has a send connecter that sends out via a Smart Host.

The VM has a standard network interface (192.168.0.9) and a WireGuard network interface for management (172.16.250.11)

When an email is sent, a Received: header is added to the message in a step prior to the Received: added by the Smart Host. When the message is sent from Exchange to itself.

Sometimes, the Received: header shows the message is received from 192.168.0.9, which is correct. However, sometimes it shows the message is received from 172.16.250.11. It appears to be random.

How can I force Exchange to only use the real network interface on 192.168.0.9 and not the pseudo adapter used by WireGuard?

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.
7,353 questions

1 answer

Sort by: Newest
Most helpful Newest Oldest
  1. Joyce Shen - MSFT 16,641 Reputation points
    2022-06-02T05:28:11.293+00:00

    Hi @Luke Kenny

    Glad to know that your issue is resolved now, and thanks for sharing the solution! I would make a brief summary of this post so that other forum members could easily find useful information here:

    [Exchange 2016 using wrong network interface - Summary]

    Issue Symptom:
    A send connecter is created to send out emails via a Smart Host. While adding the Received header of the network interface, it shows random.

    Solution:
    Specify the correct network interface using the parameter SourceIPAddress
    The SourceIPAddress parameter specifies the local IP address to use as the endpoint for an SMTP connection to a remote messaging server. The default IP address is 0.0.0.0. This value means that the server can use any available local IP address. This parameter is valid only for Send connectors configured on an Edge server.

    Reference Links:
    Set-SendConnector

    You could "Accept Answer" for this summary to close this thread, and your action would be helpful to other users who encounter the same issue and read this thread. Thanks for your understanding!

    If an Answer is helpful, please click "Accept Answer" and upvote it.

    Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

    0 comments