[Mailman-Developers] No route to host problem

[Kory Wheatley]

When I send a message to a mailman 2.1.4 mailing list using Postfix from 
a yahoo account.   I receive an error message that says "No route to 
Host".  It seems when I send out a message from our domain "isu.edu" 
they are received, but from any other smtp host I receive the below error:

/var/log/maillog:Mar 17 01:55:24 lx5 postfix/smtp[16457]: 10F74124A31: 
to=<wheakorypersonal at yahoo.com>, relay=none, delay=4956, status=deferred 
(connect to mx4.mail.yahoo.com[216.155.197.63]: No route to host)

Here's my main.cf using postconf -n ( would really appreciate help this 
is critical).
(I've been working on this for 15 hours straight and don't have any more 
troubleshooting ideas)

alias_maps = hash:/home/mailman/data/aliases
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/libexec/postfix
debug_peer_level = 2
mail_owner = postfix
mailq_path = /usr/bin/mailq
manpage_directory = /usr/local/man
mydestination = $myhostname, localhost.$mydomain, mm.isu.edu
myhostname = mm.isu.edu
newaliases_path = /usr/bin/newaliases
owner_request_special = no
queue_directory = /var/spool/postfix
readme_directory = /root/postfix_README
recipient_delimiter = +
sample_directory = /etc/postfix
sendmail_path = /usr/sbin/sendmail
setgid_group = postdrop
unknown_local_recipient_reject_code = 550
[wheakory at lx5 postfix]$ /usr/sbin/postconf -n |more
alias_maps = hash:/home/mailman/data/aliases
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/libexec/postfix
debug_peer_level = 2
mail_owner = postfix
mailq_path = /usr/bin/mailq
manpage_directory = /usr/local/man
mydestination = $myhostname, localhost.$mydomain, mm.isu.edu
myhostname = mm.isu.edu
newaliases_path = /usr/bin/newaliases
owner_request_special = no
queue_directory = /var/spool/postfix
readme_directory = /root/postfix_README
recipient_delimiter = +
sample_directory = /etc/postfix
sendmail_path = /usr/sbin/sendmail
setgid_group = postdrop
unknown_local_recipient_reject_code = 550
[wheakory at lx5 postfix]$ /usr/sbin/postconf -n |more
alias_maps = hash:/home/mailman/data/aliases
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/libexec/postfix
debug_peer_level = 2
mail_owner = postfix
mailq_path = /usr/bin/mailq
manpage_directory = /usr/local/man
mydestination = $myhostname, localhost.$mydomain, mm.isu.edu
myhostname = mm.isu.edu
newaliases_path = /usr/bin/newaliases
owner_request_special = no
queue_directory = /var/spool/postfix
readme_directory = /root/postfix_README
recipient_delimiter = +
sample_directory = /etc/postfix
sendmail_path = /usr/sbin/sendmail
setgid_group = postdrop
unknown_local_recipient_reject_code = 550

-- 
Kory Wheatley
Academic Computing Analyst Sr.
Phone 282-3874
#########################################
Everything must point to him.