Apologies but...Verizon Postmaster?

Fri Nov 21 22:42:12 UTC 2003

On Fri, 21 Nov 2003, Charles Sprickman wrote:

> On Fri, 21 Nov 2003, Jay Hennigan wrote:
>
> > In our case it's at the IP level.  Our mailserver gets "connection refused"
> > from their "business" mail servers at "bizmailsrvcs.net".  We got someone
> > on the phone who was supposed to look into it a week or so ago.
>
> Have a look at the logs on your primary MX.  Part of their "anti-spam"
> solution seems to be a connection back to your primary MXer to check if
> the envelope from is valid or not.  If you don't reply in the (very short)
> timeout period, the mail is rejected with a *permanent* failure.

Hmmm...  Our primary MX is Postini.

And they won't even open a socket on TCP 25 so we don't get far enough
to give them an envelope from.

beach% telnet mta1.bizmailsrvcs.net 25
Trying 206.46.164.22...
Connected to mta1.bizmailsrvcs.net.
Escape character is '^]'.
421 oe-mp1.bizmailsrvcs.net connection refused from [199.201.128.19]
Connection closed by foreign host.

What's weird is that any random dialup or DSL can connect to them just
fine.  It seems like they've put our mail sender in a local blacklist but
we truly hate and kill what few spammers crop up here on sight.

> It's a horrible design.  It's useless for them on MTAs that just accept
> everything into the queue and work it from there (qmail, ?) and a pain to
> the sender if you happen to have your primary mx swamped in a spam attack
> when they try to query it.  From what I can see, the timeout is *very*
> short and they do not try anything other than the primary mxer.

I think it's two different issues, as ours is at a lower level.

-- 
Jay Hennigan - CCIE #7880 - Network Administration - jay at west.net
WestNet:  Connecting you to the planet.  805 884-6323      WB6RDV
NetLojix Communications, Inc.  -  http://www.netlojix.com/