Getting Started - Connecting

Overview

Users can access the JLab Common Users Environment (CUE) by tunneling through login1 or login2 server at JLab. ssh -t -L6437:localhost:5912 cmorean@login2.jlab.org ssh -t -L5912:localhost:5912 <destination_computer>

• The red numbers should NOT be 12 for you. (That may cause our vncservers to conflict if we tunnel to the same destination_computer).
• It is common to connect to JLabl1 - JLabl3, or an ifarm computer.
• In order to use a vncserver Highly recommended over x11 port forwarding, you will need to use a computer other than an ifarm computer.

You can check your connection speed to JLab is not the problem by using JLab's SpeedTest.

Used Numbers

Once you use a number not on this list, update this list or contact someone who can. Use a number other than: 07, 11, 12, 16

VNC Server Setup

1. Insure VNC Viewer is installed on your computer.
2. Start the VNC viewer process on <destination_computer>. vncserver -geometry 1920x1080 :12
3. Open the VNC application on your computer.
   • Click file --> New connection... --> A new window should pop up
   • For IP address or host name use localhost:6437
   • Name this VNC connection anything you will remember and click Okay
4. Other Useful VNC Commands
   • To kill a VNC server on <destination_computer> vncserver -kill :12
   • To set a new VNC password vncpasswd
   • To edit the VNC window render resolution, change the numbers in blue for the command vncserver -geometry 1920x1080 :12

• The 12 should be the same number as you chose in the previous section.

Common Connection Issues

• Tunneling Problems
  • Conflicting or incorrect SSH keys in known_hosts
• VNC Server Problems
  • If you tunnel and only specifying login.jlab.org, the machine will choose either one or the other, which sometimes breaks vncservers for UNKNOWN REASONS.
  • VNC Servers should be started on the port highlighted in red using the command <vncserver -geometry 1920x1080 :<port_number>
  • VNC Servers started on different destination_computer are not accessible if you login later to some other destination_computer.
  • The computer was restarted, so the vncserver was shut down.
• JLab /group/ /work/ /volatile/ Directories Missing (Hanging)
  • Sometimes work on connection gateways will break Lustre file system connections that are not tier-1
  • Improper JLab farm node use can cause the Lustre file system to hang. Report an incident report using the Incident Report Utility