su with X forwarding

Background

Recently I started working more on linux systems that require X windows to run, mostly due to GUI installers. I am not new to the idea of X forwarding over SSH, and I am not new to the idea that some installers must be run as certain users — But this was a first for me where the graphic installer had to be run on a remote machine, and had to be run as a user with no password.

My Setup

Running Mac 10.9.2 (Mavericks)

Standard Mac Terminal with XQuartz for my X windows display

Steps

1. Login to your remote server

   ssh -X user@remotehost.com
   

2. List your xauth

   $ xauth list
   remotehost.com/unix:10  MIT-MAGIC-COOKIE-1  c11dec3114034d20d92e839581bc7a2c
   remotehost.com/unix:11  MIT-MAGIC-COOKIE-1  ccf459946111123cf8d111cc6795d3e8
   

3. If more than one are listed echo your DISPLAY

   $ echo $DISPLAY
   localhost:11.0
   

4. Select and copy the correct line

5. Switch user

   $ sudo su - remoteuser
   [sudo] password for user:
   
   remoteuser $
   

6. Add the xauth

   remoteuser $  xauth add remotehost.com/unix:11  MIT-MAGIC-COOKIE-1  ccf459946111123cf8d111cc6795d3e8
   

7. Run your remote GUI app

   remoteuser $  ./someLameGUI