Re: Accepting external sendmail on 2.0.2

From: Igor Sobrado (igor_at_string1.ciencias.uniovi.es)
Date: 07/05/05 

Date: 5 Jul 2005 16:50:05 +0200

Frederick Bruckman <fredb@immanent.net> wrote:
>
> If you only have one interface, or if you don't mind listening on all
> the ones you do have, "address=0.0.0.0" should work, too -- or simply
> comment out that line. The point of that line in the default config
> is to let programs such as "cron" invoke "sendmail" or "mail", and
> let them "just work", without enabling a listener on the network. Of
> course, if you're setting up a mail server, it's a different story.

I think that sendmail listening in the loopback interface by default
is a *fine* decision. It is useful (required!) for "vi" too, and it
is the best method for retrieving email in a secure way using
fetchmail too. Certainly, sendmail should be listening in the
loopback interface by default on all systems, and listening on
external interfaces only on real mail servers.

I like the default NetBSD configuration, without processes listening
to the external interfaces.

Is there a reason X11 listens to external interfaces by default when
X is running? I have closed it:

  $ cat .xserverrc
  #!/bin/sh

  PATH=/usr/X11R6/bin
  exec X :0 -dpi 100 -nolisten tcp

and see no differences (telnet daemon is closed by default, and ssh
does not really require these 6000+x ports opened). Is it reasonable
asking these ports to be closed by default?

Cheers,
Igor.

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