Nginx mail proxy

[Maxim Dounin]

Hello!

On Sat, Mar 21, 2015 at 12:37:40AM -0400, imwack wrote:

> I want to use nginx as a mail proxy.I am new to nginx and need some help
> with the configuration, I got some problems.
> I want to use Foxmail ,use ngx proxy , this is my configuration.

[...]

> But this does not run,when i use telnet test,as follow
> telnet 192.168.42.132 25
> Trying 192.168.42.132...
> Connected to 192.168.42.132.
> Escape character is '^]'.
> 220 wack ESMTP ready
> auth login
> 334 VXNlcm5hbWU6
> base64(username==)
> 334 UGFzc3dvcmQ6
> base64(password)
> 451 4.3.2 Internal server error
> Connection closed by foreign host.
> 
> what's wrong ,and the error log as follow:
> 
> 2015/03/21 12:35:39 [error] 55719#0: *151 upstream sent invalid response:
> "550 insufficient authorization" while reading response from upstream,
> client: 192.168.42.132, server: 0.0.0.0:25, login: "***@**.**.cn",
> upstream:***.***.***.***:25
> 
> The '*' is my username and backend ip.  192.168.42.132 is my vitual machine
> ip.

When using SMTP, nginx won't try to do any authentication against 
the backend server, but rather will use XCLIENT command to pass 
user credentials, see http://nginx.org/r/xclient.  You have to 
instruct your SMTP backend to accept XCLIENT from nginx.  When 
using Postfix, this can be done with 
smtpd_authorized_xclient_hosts:

http://www.postfix.org/postconf.5.html#smtpd_authorized_xclient_hosts

-- 
Maxim Dounin
http://nginx.org/