Upgrading from Redhat 7.3 to 8.0

[Adam Myrow]

Actually, Redhat was blocking sendmail in 7.2.  I'm pretty sure of this
because I didn't know how to configure sendmail to not let any outside
connections in.  I wanted this because I only use sendmail for the back
end to fetchmail to retrieve my mail from my ISP and to send out mail from
the command line.  So, I looked at Redhat's configuration file and copied
the line out of it to mine.  BTW, the magic line is
DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')
which makes sendmail only listen to localhost.  This is a good thing for a
home user, not so good for a server which needs to be able to accept mail
from the Internet at large.  Hope this helps.