Re: How do I disable (close) ports?

[chris@darkzone.lnp.org]

Hi Paul,

On Tue, Dec 04, 2001 at 09:18:09PM +0100, J. Paul Bruns-Bielkowicz wrote:
> Hi,
> I disabled all but a few ports in /etc/services, but I have
> tcp        0      0 pa237.olsztyn.sdi.t:111 80.116.215.37:1064
> ESTABLISHED
> when I netstat my machine. What exactly does this mean? I just want
> 25/tcp     open        smtp
> 37/tcp     open        time
> 66/tcp     open        sql*net
> 80/tcp     open        http
> 110/tcp    open        pop-3
> 443/tcp    open        https
> 3306/tcp   open        mysql
> open. How can I close ports 111 and 859? They are not enabled in
> /etc/services

may you take a look at the corresponding man pages:
services, inetd.conf and inetd:
       (services...)
       services is a plain ASCII file providing a mapping between
       friendly textual names for internet  services,  and  their
       underlying assigned port numbers and protocol types.
       ...
       The  presence  of  an  entry for a service in the services
       file does not necessarily mean that the  service  is  cur-
       rently  running  on the machine. See inetd.conf(5) for the
       configuration of Internet services offered. Note that  not
       all  networking  services  are started by inetd(8), and so
       won't appear in inetd.conf(5).  In particular, news (NNTP)
       and  mail  (SMTP)  servers  are often initialised from the
       system boot scripts.
       ...

A port is "open" if there is a programm listening on it and answering 
incomming requests. It has nothing to do whether it is mentioned in
/etc/services or not.

Hope this helps and fit your needs
regards
chris