[NCLUG] Two easy? security questions...

[Aaron Johnson]

> > X can be told not to listen for TCP connections.  Add a '-nolisten
> > tcp' to the X server's command line.  If you want connections from
> > remote hosts, this does screw up the usual 'xproggie -display
> > myremotexserver:0' approach, but ssh serves nicely instead.
> 
> Where should one add the "-nolisten tcp" flag if X is being started
> "automagically" (eg, runlevel 5 on a RH-like system)?

Not entirely sure on your setup.  RedHat actually starts a (sadly
undocumented (at least on the 6.1 box I use most often)) program
called "prefdm" which tries to figure out which of gdm, kdm, and xdm
to run.  I'm running gdm, and have this in the [servers] section of my
gdm.conf:

    0=/usr/bin/X11/X :0 -nolisten tcp -bpp 32 -dpi 100 dpms vt9

Not sure about doing that with xdm or kdm, but it should be documented
in a man page or doc file somewhere.

HTH.

Aaron
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