nanog mailing list archives

Re: Where does "Downstream server error" come from?


From: Brielle Bruns <bruns () 2mbit com>
Date: Sun, 19 Jan 2014 18:02:22 -0700

On 1/19/14, 5:32 PM, Scott Howard wrote:
I've come across this error (or something very similar to it) before.  I
can't remember the exact product, but it turned out to be a transparent
SMTP proxy somewhere in the path - possibly on a UTM firewall, but I could
be wrong about that part...

Not overly helpful I know, but might point you in the right direction...



Almost sounds like one of those annoying consumer Antivirus programs with the smtp/imap/pop3 proxies that wedge themselves in between mail client connections.

Trying to remember what the error it was giving the other day on the machine I worked on, when the proxy itself had been blocked by the local system's firewall...

I'd have been curious if you got the same error message trying to go out on 587 instead of 25.

Thinking about it, that error screams of something like what a multi-server Exchange setup would say if something went wrong on the backend.


Not entirely helpful either, but...  never know.


--
Brielle Bruns
The Summit Open Source Development Group
http://www.sosdg.org    /     http://www.ahbl.org


Current thread: