HPC/Network Access/PuTTY Configuration

Introduction

The Carbon cluster is reachable from networks outside Argonne only through SSH tunneling or VPN. Either way has advantages and disadvantages. This page explains how to connect through an ssh tunnel.

Tunneling is a two-step process:

1. Establish the tunnel.
2. Connect through the tunnel.

Overview slides (pdf) and specifics for Carbon are detailed elsewhere. The PuTTY setup for both steps is illustrated below.

Note that the PuTTY Configuration panel is somewhat idiosyncratic to operate, notably regarding the concept of Sessions. Numerous screenshots on Google provide general guidance.

Configuration

Configure first session

1. Open PuTTY. The PuTTY Configuration window will appear.

   

   There are many configuration panels that will appear in the main part of the window. The panels are organized as a tree, shown in the left-hand side of the window. Each panel can be reach by clicking on the leaf names of the tree.

2. If you already have a session named Mega shown in the bottom right list of the main panel, push the Load button.

   

3. Click Data in the tree. In the Login details section of the panel enter your username.
   • Auto-login username: username

   

4. Click SSH in the tree
5. Click the checkbox Don't start a shell or command at all in the Protocol options section.

   

6. Click the "+" symbol near SSH to open its sub-tree.
7. Click Tunnels. Under Add new forwarded port, enter:
   • Source port: 33301
   • Destination: clogin:22
   • Push the Add button. A new entry will appear in the middle field, shown as:

     L33301 clogin:22

     The letter "L" denotes a port on the local host.

   

8. Scroll to the top of the tree and click Session. Enter the host details:
   • Host name: mega.cnm.anl.gov
   • Port: 22 (leave at the default).
   • Protocol: SSH (leave at the default).
   • In the Saved Sessions field, enter Mega
   • Push Save. The entry will appear in the list of saved sessions.

   

Configure second session

1. In the PuTTY Configuration window, click Session at the top of the tree on the left.
2. Select the Mega session and push Load. This session will be the basis for the next steps.
3. Click SSH in the tree
4. Uncheck the checkbox Don't start a shell or command at all.
5. Click X11 in the tree.
   • Click the checkbox Enable X11 forwarding.
   • Set X display location to :0

   

6. Click Tunnels.

• Select the L33301 entry and push Remove. There should be no forwarded ports listed.

1. Under Add new forwarded port, enter:
   • Source port: 6200
   • Destination: mgmt03:6200
   • Push the Add button.
2. Repeat with the following settings:
   • Source port: 6201 (not 6200!)
   • Destination: mgmt04:6200
   • Push the Add button.
3. Repeat once more as follows:
   • Source port: 6202
   • Destination: sched1:6200
   • Push the Add button.

   You should see tree entries:

• • L6200  mgmt03:6200
  • L6201  mgmt04:6200
  • L6202  sched1:6200

1. 

2. Scroll to the top of the tree and click Session. Enter the host details:
   • Host name: localhost
   • Port: 33301 (referring to the tunnel set up above as L33301.)
   • Protocol: SSH (leave at the default).
   • In the Saved Sessions field, enter Clogin
   • Push Save. The entry will appear in the list of saved sessions.

   

Connecting to Mega

1. In the PuTTY Configuration window, click Session at the top of the tree on the left.
2. Select the session named Mega and push Load.
3. Make sure the Host Name field shows mega.cnm.anl.gov.
4. Push Open.

   

5. When prompted, enter your Argonne account password. When accepted, the cursor will wait at the next line and nothing further will happen.

   

6. Minimize the window.

Connecting to Carbon itself

1. Open another PuTTY window.
2. Select the session named Clogin and push Load.
3. Make sure the Host Name field shows localhost.

   File:HPC 2012-08 PuTTY config 13 Load clogin.png

4. Push Open.
5. Welcome to Carbon! - You should get our NOTICE TO USERS and a prompt saying login5 or login6 followed by /home/username.

Setup for step 2