[plug] apologies, real n00b question.

[Nick Bannon]

On Thu, Dec 08, 2005 at 04:06:36PM +0800, Richard Meyer wrote:
> I need to start up another instance of X on my PC - want to run db2
> admin tools, and it wants its own access to the desktop

To answer your question - "how do I start up another instance of X?" -
"startx -- :1" from a text console; or it looks like you can switch users
in KDE. (3.4 or later) Login as db2inst1 (that's the user you're trying to
run things as, right?) in your new session and run things as you expect.

http://gentoo-wiki.com/TIP_Run_multiple_KDM_instances

You can have any number of applications from different users and different
machines sharing the one X server session, that's what the DISPLAY,
xhost, xauth settings are all about. However, these days, everything
gets locked down by default. The X server doesn't listen to the network
(-nolisten tcp, DisallowTCP in /etc/X11/gdm/gdm.conf); once you fix that
you need to use xhost or copy around your cookie (a kind of random password
for your X session).

http://nst.sourceforge.net/nst/docs/faq/ch08s04.html
http://www.tldp.org/HOWTO/Remote-X-Apps-6.html

But! The easiest thing to unlock is SSH X forwarding. A bit of a waste
of CPU, but it works:

1. Edit selous:/etc/ssh/sshd_config to say:
  X11Forwarding yes

2. Restart SSH:
  /etc/init.d/sshd restart

3. Login with "ssh -X":
  $ echo $DISPLAY
  :0
  $ ssh -X db2inst1 at selous
  db2inst1 at selous's password:
  [...]
  db2inst1 at selous:~> echo $DISPLAY
  localhost:10.0
  db2inst1 at selous:~> xauth list
  selous/unix:10  MIT-MAGIC-COOKIE-1  b69ddcfbbd8019a06d28c0b9d625db09
  db2inst1 at selous:~> db2fs &

Nick.

-- 
   Nick Bannon   | "I made this letter longer than usual because
nick-sig at rcpt.to | I lack the time to make it shorter." - Pascal