Ok, making progress
I had to make sure /etc/mail did not have group write permissions.
then following your advice I did
sudo domainname dyndns.org
sudo hostname my_dyndns_subdomain
sudo /usr/sbin/sendmail -bd -q1h &
and I could finally telnet to port 25.
Fetchmail was then able to retrieve my POP mail.
I tried outgoing mail and did not have any luck.
I found that I needed to set hostname to my full hostname, not just the machine under the domain. As far as I could tell domainname wasn't being picked up at all (my mail was coming from me@hostname only, not me@hostname.domainname as I thought it might).
Anyway, at this point, outgoing mail works.
Fetchmail can now retrieve outside mail. I'm having a mailbox lock problem with elm, but I guess I can pound on that.
So I tried sending myself some mail (to zimmy@zimmy.dyndns.org)
My mail I send from an outside acct bounces... and I get a message about mail relaying being denied... that _could_ be RoadRunner filtering port 25?
So from my machine I telnet to port 25
mail from: me@outside.isp
rcpt to:zimmy
data
testing
.
Oh, I also found that I needed to set host = myhost
And that works. So I guess RR is blocking incoming port 25?
Thanks for the help,
Mike