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Mohammad_1363's avatar
Mohammad_1363
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May 06, 2020

How to send the client IP to the SMTP servers

Hello

I have deployed some smtp servers in my network, I placed them behind the F5s, when applications start using the smtp service, we do not see the application IP (client IP) coming to the smtp server.

I am using SNAT pool in my F5s, so when the client initiate the connection as you know, F5 proxy the connection and establish a new connection from its SNAT pool, therefore smtp is seeing the F5 SNAT IP.

I can not  set back-end server to use the BigIP floating IP as the Default GW.

what other option do I have, possibly iRule ?

 

Regards

2 Replies

  • So I've found this post if you're running postfix. https://devcentral.f5.com/s/question/0D51T00006i7fLo/xforward-for-smtp look at the last comment. I too have this issue and I feel like there would be a better way to solve this.

  • Thanks for your reply, I am not using postfix.

    let me know if you have any other suggestion.

     

    Regards