which port(s) does the X server listen on?

[Douglas Frank]

On Fri, 2005-02-11 at 16:19 -0500, Scot L. Harris wrote:
> 
> Most of the time one would ssh to the box they want to run the
> application on then start that application.

That's what I'm doing.  With xhost + at the server and the firewall
disabled, I get "Can't open display" (and yes I've got DISPLAY set
correctly).  With the firewall enabled, I get the same thing although it
takes a while longer to give up.

> 
> The things you may run into include:
> 
> 1. on local machine you will need to allow other systems to display X
> windows on your local machine.  This is done via the xhost command as
> you already found out.

right

> 2. you will need to open up port 22 (or whatever port you have
> configured) for ssh access on the remote system.

OK I'll do that... well I just OK'd port 22 with tcp & udp both, using
the KDE "security level" tool and although it didn't complain, it also
doesn't stick.  On re-opening the applet, those port settings are gone.

> 3. Starting with FC3 you will most likely need to specify either -Y or
> -X as options on the ssh session to get it to connect successfully.

Thanks for the tip, although it doesn't have an effect on my present
case.

> 4. The first time you connect you will be prompted to setup an
> certificate or key with that system.  If the machine has been locked
> down tight you may not be able to do this on the fly, it may require you
> to copy the certificate to the known_hosts file by hand.  But the
> default setup should let you do this on the fly.

Oops, I didn't have a key handy and just took the default, which allowed
me in anyway.  Was that a mistake?

> 5. The display variable must be setup on the remote system correctly.

Yup, that's one thing I *did* know about  :-}

-- 
Douglas Frank    HP Co.
ZKO              110 Spit Brook Rd.       The older I get,
603-884-0501     Nashua, NH USA 03062       the better I was.