> telnet on the other hand is usually run by inetd (or xinetd etc). This
> means inetd listens on port 23 and when a connection is attempted it
> accepts and starts the telnet daemon. In this case you must configure
> inetd not to listen on that port (/etc/services) and/or not to connect a
> daemon to it (/etc/inetd.conf). I would guess the former is strictly
> cleverer as inetd is not exposed either.
It is a common misconception that removing lines from /etc/services
inetd does not listen on ports according to the /etc/services file.
It listens on the ports that have entries in /etc/inetd.conf.
/etc/services is merely a name-to-number mapping file for ports.
So that when you do (for example):
$ telnet somehost smtp
it can convert "smtp" to 25. Also when you do:
it can convert 25 to "smtp".
And /etc/services can be centralised via NIS (and probably also
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