[Techtalk] RH7.2 Server Question

[Samantha]

On Wednesday 24 April 2002 03:14 pm, a magikal owl from Kai MacTane delivered 
this message:
> At 4/24/02 01:01 PM , Samantha wrote:
> >--- Kai MacTane <kmactane at GothPunk.com> wrote:
> > > Do you have some kind of firewalling set up?
> >
> >Yes, but it is set to allow telnet.
>
> The firewall distinguishes "telnet" by what port it's destined for. This
> means it will only allow connections to port 23. To get it to allow
> connections to ports 22 and 25, you'll need to set your firewall rules to
> allow connections to smtp and ssh. (I'm not sure if your firewalling
> software's UI does this by port number or by service name, so either "ssh"
> and "smtp", or 22 and 25.)
>
> Basically, neither your firewall nor any other part of your server can tell
> what particular client program is being used on the other end of the
> connection; a telnet connection to port 25 looks just like a "real" SMTP
> connection, except that it proceeds at human typing speed instead of
> super-fast computer speed. Or, to look at it another way, a program
> actually connects to an SMTP server by forming a telnet connection to it.
>
>                                                  --Kai MacTane

*nods* It is set to allow both ssh and smtp connections as well. I will 
double check because I have a bad habit of misremembering the ways that I 
actually set things, but I do distinctly remember setting it to allow 
conntections to those ports because I remember thinking how insecure but 
doing it anyway.

Samantha