VisIt at Brookhaven National Lab

You will need to install VisIt on your local machine in order to follow the instructions below. You can download VisIt executables for standard Linux distributions, Windows, and Mac OS X at www.llnl.gov/VisIt.

These instructions are for setting up a Host profile to run VisIt (1.9.x) remotely on BNL's Visualization Cluster. These instructions also assume you have read instructions on how to setup remote access via SSH-Tunneling to BNL.

  1. Set up a machines file so that MPICH knows which nodes are participating in the cluster:
    1. Edit ".machines" in your home directory and add the following lines: vis1Gpfs:8
      vis2Gpfs:8
      vis3Gpfs:8
      vis4Gpfs:8
  2. Set up passwordless SSH on the Visualization Cluster:
    1. Create a new ssh key pair: ssh-keygen -t dsa
    2. Enter a filename to store the key pair. (If you haven't already used the default on this filesystem, just use that.)
    3. You don't have to type anything for the passphrase, just hit enter.
    4. Append your public key to the authorized keys file: cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys
    5. Run: ssh-agent > ~/.sshagent
      source ~/.sshagent
      ssh-add ~/.ssh/id_dsa
    6. Now you should be able to SSH without a password between nodes of the Visualization Cluster
  3. Run the MPICH Daemon process: mpdboot -n 4 -f ~/.machines Stop the MPICH Daemon process when you are done: mpdallexit
  4. Create a Host Profile for BNL's Visualization Cluster in VisIt:
    1. Open VisIt on your local machine
    2. Click Options -> Host Profiles
    3. Click "New profile". The following are BNL specific settings categorized by tab in the Host profiles window:
      1. "Selected profile" tab:
        1. Name your profile whatever you want
        2. Remote host name: 127.0.0.1
          (this should be your loopback address) You cannot simply put localhost, because VisIt will attempt to resolve the name to the local computer's hostname.
        3. Username: enter your username
        4. Check the box next to "Parallel computation engine"
      2. "Parallel options" tab:
        1. Default number of processors: 32
        2. Default number of nodes: 4
      3. "Advanced options" tab:
        1. Under Networking, check the box for "Tunnel data..."
        2. Check the box for "Specify SSH port" and set it to 30023.
          (This is the port we forward to the Visualization Cluster)
  5. Now you can connect by trying to select the files you want to view on the Visualization Cluster.
    1. File -> Select File ...
    2. From the pulldown menu, select 127.0.0.1
    3. Navigate to your data file and proceed as if you were visualizing data that was on your local machine