Re: [cobalt-users] Maybe Not a Raq ??

[Parker Morse <morse@xxxxxxxxxxx>]

On Thursday, December 12, 2002, at 03:02  PM, Jerry Farquhar wrote:
> What is the best way of checking for some kind of Black Listing for a
> domain???

http://relays.osirusoft.com/cgi-bin/rbcheck.cgi?addr=sub.domain.tld

where sub.domain.tld is the name your mail server gives in HELO, or the IP 
address of your SMTP server, or whatever.

Assuming your user's mail gets to your RaQ (and it probably does, if they 
can mail anyone else, including you), the problem must be somewhere 
between you and the destination server. Here's what I'd do, using "target.
dom" as the domain that's not receiving your mail:

SSH in to your RaQ.

$ dig mx target.dom
# find the name of their mail server, let's say this gives us mail.target.
dom

$ dig mail.target.dom
# gets us an IP address for mail.target.dom, let's say 127.0.0.1

$ telnet 127.0.0.1 25
# (following edited from a "conversation" I had with a mail server 
recently doing something very similar; anything after the greeting 
starting with a number came from the remote server, the rest is my input.)
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
220 mail.target.dom -- Server ESMTP (PMDF V6.0-24#41763)
HELO mail.clientdomain.net
250 mail.target.dom OK, admin@xxxxxxxxxxxx [your.ip.here.xx].
mail from: client@xxxxxxxxxxxxxxxx
250 2.5.0 Address Ok.
rcpt to: address@xxxxxxxxxx
250 2.1.5 address@xxxxxxxxxx OK.
# You'd best bail out at this point, or you're sending a real mail message 
to address@xxxxxxxxxxx
quit
221 2.3.0 Bye received. Goodbye.
Connection closed by foreign host.
$

If that works... then one of two things is wrong. (a) Your sendmail and 
their SMTP server don't like each other. This is very unlikely, IMHO. (b) 
There's something else happening after the mail is accepted by mail.target.
dom which /dev/null's your client's mail... in which case it's out of your 
hands, because you've done all you can by getting the message as far as 
mail.target.dom.

If I've missed something here, I'm sure someone will tell me... :-)

pjm