Re: Mail routing Issue

[rob@xxxxxxxxx]

Testing from home, or elsewhere, the telnet to port 25 still bears some 
utilization.  If they have multiple ?? records only a few of them may be 
putting a block on you.  For example, let's say your vendor was ibm.com. 
I'd go to
http://www.zmailer.org/mxverify-cgi.html
and type in ibm.com in the first field.
Then, I'd telnet to the IP address shown for each of these
  ibm.com  (3600s) IN MX  10 e1.ny.us.ibm.com
  ibm.com  (3600s) IN MX  10 e2.ny.us.ibm.com
  ibm.com  (3600s) IN MX  10 e3.ny.us.ibm.com
  ibm.com  (3600s) IN MX  10 e4.ny.us.ibm.com
  ibm.com  (3600s) IN MX  10 e5.ny.us.ibm.com
  ibm.com  (3600s) IN MX  10 e6.ny.us.ibm.com
  ibm.com  (3600s) IN MX  10 e31.co.us.ibm.com
  ibm.com  (3600s) IN MX  10 e32.co.us.ibm.com
  ibm.com  (3600s) IN MX  10 e33.co.us.ibm.com
  ibm.com  (3600s) IN MX  10 e34.co.us.ibm.com
  ibm.com  (3600s) IN MX  10 e35.co.us.ibm.com
Like
 IPv4 32.97.182.141
Testing server at address: IPv4 32.97.182.141
ERROR: Connect failure reason: Connection refused

Now, many people do have multiple MX records like this.  And often the 
first one will be a failure.  It is a published fact that having the first 
one on the list be somewhat hosed will help to stop SOME spam because they 
will only attack the first one. 

Rob Berendt