IP6tables and sendmail

[Deron Meranda]

> > While we are on the subject, I courious how many of you folks out there
> > acutally installed and configured iptables-ipv6 (or disabled IPv6) on
> > your firewall boxes, and how many of you are wide open?

I use IPv6 all the time.  I do have sendmail gateways configured to
use it, DNS, etc.  I haven't yet though disposed of my IPv4 stack. 
Someday...


> Thanks for your assistance.  I turned IP6 off of the FC3 unit but still could not use
> sendmail, so I decided to turn IP6 on for both the FC3 and RH8 system.  Unfortunately
> the sendmail ntp symptoms have not changed.

I sounds like you are having some other issue.  This whole IPv6 theory
may not have anything to do with it.

What do you mean by the "ntp" symptoms?  What's the output of running
"ntpq -c peers"?

The most puzzling thing is that you said a 'telnet xxx 25' works.  So,
here's some things we need to try:

1. Look up MX records, etc.

   $ host -t mx rh80host.yourdomain.com.
   $ host -t mx yourdomain.com.
   $ host -t a rh80host.yourdomain.com.

2. Get the qf* file.  When you attempt to send mail and it's refused,
does it stay queued for delivery?  Run,

   # sendmail -bp

If you see it listed in there, get the queue number and go find the
corresponding qf* file under /var/spool/mqueue.

3. How heavily cusomized are your systems.  Like your sendmail.mc
file.  iptables and ip6tables?  Are you running any sendmail milters?

-- 
Deron Meranda