Re: [exim] socks inbound connection problems

Top Page
Delete this message
Reply to this message
Author: Jeremy Harris
Date:  
To: exim-users
Subject: Re: [exim] socks inbound connection problems
On 01/03/2021 16:28, Alex via Exim-users wrote:
> I've installed exim on a Debian machine with only a private IP. Outbound connections go trough a socks proxy. As regards inbound connections, I'm forwarding connections from a public IP from a VPS towards the private IP of my server.
>
> The problem I noticed is that when I receive an email, my server replies to the EHLO command like if the sender was my own local server.
>
> I tested my server on mxtoolbox, and this is what I see:
>
> 220 mail.my-fqdn ESMTP Exim 4.92 Mon, 01 Mar 2021 17:20:54 +0100 [257 ms]
> EHLO keeper-us-east-1b.mxtoolbox.com
> 250-mail.my-fqdn Hello mail.lan [192.168.0.216]  ### these are my local domain and private IP address
>
> Is this something that could impair my domain/ip reputation?


While one can never account for what other people think, I'd say
"not in any significant amount". They are more likely concerned
about mail you send them, than mail connections they make to you.

But it *will* confuse anyone trying to debug at issue sending you mail.

> Could you please give me some clue on how I could fix this?


Run a Proxy-protocol proxy on your VPS rather than a bare
port-forward. You'll need to configure your Exim to know
about it. Then Exim will know the IPs visible to the outside world.



Refs:

https://www.haproxy.com/blog/haproxy/proxy-protocol/
http://exim.org/exim-html-current/doc/html/spec_html/ch-proxies.html
--
Cheers,
Jeremy