Paul Rockwell solved my puzzle. I did what he suggested (below) and found that
our corp people do have the MX records set to this mystery machine.
thanks again.
Original ?:
----------------------------
I have some stupid sendmail questions. Thanks in advance to any help here.
I have a 3.2a system set up and I'm able to send mail out to the internet via
a corp mail gateway. When I did a mailsetup, I did NOT specify a relay
machine.
I used mailx -v a while ago, and watched my sendmail connect to a machine, do
the greeting thing, and then pass the message on. The machine my sendmail
connected to doesn't seem to be defined anywhere on my system. I can nslookup
this relay machine, but I can't find anywhere that it's defined as the place to
forward my mail. I don't know much about sendmail and SMTP. Is there a place
where this information is defined?
Replies:
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"Paul E. Rockwell" <rockwell_at_rch.dec.com>
Probably your system administrators have DNS MX (Mail eXchanger) records set
up to send all non-local mail to your relay machine. sendmail will use
these MX records, if present, to assist in routing mail.
You might want to verify this by doing the following:
$ nslookup
> set type=mx
Now type in a host name that's not in your domain (gatekeeper.dec.com is one
that comes to mind readily ;-) )
You should see some messages containg a preference, and a mail exchanger
host. Then comes messages equating an IP address with the mail exchangers
that nslookup has shown you.
If it shows that the mail exchanger is your mail relay machine, then you've
found the source of your puzzling behavior.
pobrien_at_draco.harvard.edu (Patrick O'Brien)
Here's a generalization; the specifics of your sendmail are in
your sendmail.cf, and without that, one can't answer definitively.
If sendmail knows how to connect directly to a host, it will do that; if
not, it looks for a host aliased to mailhost. If you're running YP,
try ypcat -k hosts | grep mailhost. If you're using /etc/hosts,
grep mailhost there.
Received on Tue Jul 25 1995 - 23:26:34 NZST