Remote access

PQSetup can run beside PQ and its calculators on a server while you use the browser on your desktop. Keep the HTTP server on its default loopback address; the SSH tunnel provides access without exposing PQSetup to the network.

Direct SSH

On the server, activate the environment containing PQSetup and start it without opening a remote browser:

pqsetup serve --no-browser --port 8888

Keep that command running. In a second terminal on your desktop, open the tunnel:

ssh -N -o ExitOnForwardFailure=yes \
  -L 127.0.0.1:8888:127.0.0.1:8888 user@server

Then open http://localhost:8888 on the desktop. Keep the SSH command running while you use PQSetup. ExitOnForwardFailure reports a failure to create the local listener; it does not verify that PQSetup is healthy on the server.

Work from home through the institutional VPN

  1. Connect to the institutional VPN.

  2. Confirm the server is reachable with ssh user@server. If this fails, resolve the VPN, DNS or SSH access problem before starting a tunnel.

  3. Start PQSetup on the server with the command above.

  4. Run the same tunnel command from the desktop and open http://localhost:8888.

If the VPN disconnects, reconnect it and run the tunnel command again. The PQSetup process must still be running on the server.

Login node and compute node

When PQSetup runs on a compute node inside an active allocation, start it on that compute node:

pqsetup serve --no-browser --port 8888

If the site permits SSH to compute nodes through a login node, run this on the desktop:

ssh -N -o ExitOnForwardFailure=yes -J user@login.cluster \
  -L 127.0.0.1:8888:127.0.0.1:8888 user@compute-node

The SSH destination must be the node hosting PQSetup. Forwarding to the login node does not reach an app bound to a compute node’s loopback interface. Keep the allocation, PQSetup process and tunnel alive. Follow the site’s access policy when direct SSH to compute nodes is not permitted.

Files and environment

PQSetup runs in the remote process. Command-line paths, PATH, PQ_EXECUTABLE, saved configuration and calculator discovery therefore refer to the server or compute node. The browser still runs on the desktop: files selected in it are uploaded through the encrypted tunnel for processing, and downloaded run packages return to the desktop.

Troubleshooting

  • If ssh user@server fails from home, check the VPN connection, institutional DNS and routes, then the SSH host name and account.

  • If local port 8888 is occupied, keep PQSetup on remote port 8888 and use a different desktop port:

    ssh -N -o ExitOnForwardFailure=yes \
  -L 127.0.0.1:18888:127.0.0.1:8888 user@server

    Open http://localhost:18888.

  • If the tunnel starts but the page does not load, confirm PQSetup is still running on the SSH destination and that the command uses the node hosting the app. A successful local forward does not prove remote app health.

  • After a VPN interruption, reconnect the VPN and restart the SSH tunnel.