HPC/Network Access/Virtual Desktop: Difference between revisions

From CNM Wiki
Jump to navigation Jump to search
m (Created page with "== Introduction == [http://en.wikipedia.org/wiki/VNC VNC] is a multi-platform graphical remote access mechanism. It is not as common as the [http://en.wikipedia.org/wiki/X_Window…")
 
Line 4: Line 4:
If you find that remote use over X11 is too slow, try VNC.
If you find that remote use over X11 is too slow, try VNC.


TO BE CONTINUED
== Principle of operation ==
* Start a VNC server on a Carbon node. This is an application that will run in the background and provide a virtual desktop.
* Modify your SSH connection to forward an appropriate port.
* Run a VNC client on your desktop machine and tell it to connect to the forwarded port. This will show the virtual desktop as a window on your actual desktop.
* You can stop the VNC client and reconnect later.
* When done, kill the VNC server process on Carbon.


* http://www.cl.cam.ac.uk/research/dtg/attarchive/vnc/sshvnc.html
=== VNC server startup ===
* [[https://wiki.anl.gov/cnm/HPC/Network_Access Log in to Carbon]] as documented.
* On the clogin prompt (showing login5 or login6), enter:
vncserver
* You may be asked for a password which will control access to a virtual desktop session. Choose and remember a password of good strength, but '''not your login password'''. The VNC password mechanism is weak; think of it as an office door to shut, keeping out unwanted guests.
* To reset your password at any time, run:
vncpasswd
* Note the output of the vncserver command:
New 'login5:1 (stern)' desktop is login5<font color="teal">''':1'''</font>
Starting applications specified in /home/stern/.vnc/xstartup
Log file is /home/stern/.vnc/login5:1.log
The number after the <code>:</code> is the <font color="teal">''display number''</font> of your virtual desktop.
 
=== Forward SSH ports ===
Forward a (TCP) port from your machine to the same port on the Carbon login node. How to do that depends on the SSH program you use.
; For Linux and Mac:
* Press <code><Enter>~C</code> (three keys in succession: Enter, tilde, capital C). You should get a prompt like this:
ssh>
* At the prompt, enter:
-L ''port'':localhost:''port''
: where <code>''port''</code> = 5900 + <font color="teal">displaynumber</font> from above, for example:
ssh> -L <font color="teal">'''5901'''</font>:localhost:<font color="teal">'''5901'''</font>
Forwarding port.
* Press <code><Enter></code> to regain your regular prompt.
 
; For PuTTY on Windows: TBD
 
=== VNC server teardown ===
vncserver -kill :''displaynumber''
 
<!-- http://www.cl.cam.ac.uk/research/dtg/attarchive/vnc/sshvnc.html -->

Revision as of 00:16, October 5, 2012

Introduction

VNC is a multi-platform graphical remote access mechanism. It is not as common as the X Window System but is more light-weight on the user side and over the network. If you find that remote use over X11 is too slow, try VNC.

Principle of operation

  • Start a VNC server on a Carbon node. This is an application that will run in the background and provide a virtual desktop.
  • Modify your SSH connection to forward an appropriate port.
  • Run a VNC client on your desktop machine and tell it to connect to the forwarded port. This will show the virtual desktop as a window on your actual desktop.
  • You can stop the VNC client and reconnect later.
  • When done, kill the VNC server process on Carbon.

VNC server startup

  • [Log in to Carbon] as documented.
  • On the clogin prompt (showing login5 or login6), enter:
vncserver
  • You may be asked for a password which will control access to a virtual desktop session. Choose and remember a password of good strength, but not your login password. The VNC password mechanism is weak; think of it as an office door to shut, keeping out unwanted guests.
  • To reset your password at any time, run:
vncpasswd
  • Note the output of the vncserver command:
New 'login5:1 (stern)' desktop is login5:1

Starting applications specified in /home/stern/.vnc/xstartup
Log file is /home/stern/.vnc/login5:1.log

The number after the : is the display number of your virtual desktop.

Forward SSH ports

Forward a (TCP) port from your machine to the same port on the Carbon login node. How to do that depends on the SSH program you use.

For Linux and Mac
  • Press <Enter>~C (three keys in succession: Enter, tilde, capital C). You should get a prompt like this:
ssh>
  • At the prompt, enter:
-L port:localhost:port
where port = 5900 + displaynumber from above, for example:
ssh> -L 5901:localhost:5901
Forwarding port.
  • Press <Enter> to regain your regular prompt.
For PuTTY on Windows
TBD

VNC server teardown

vncserver -kill :displaynumber


Retrieved from "https://wiki.anl.gov/wiki_cnm/index.php?title=HPC/Network_Access/Virtual_Desktop&oldid=4024"