SSH

Config File

An SSH config file named sherpa_ssh_config is created per-lab which is used by the sherpa ssh <node-name> command to access lab nodes.

Users SSH Config File

To allow seamless conectivity to lab nodes, the users ssh config file in ~/.ssh/config will have a line added: Include <home_dir>/.ssh/sherpa_lab_hosts to the top of the file.

The sherpa_lab_hosts file has Include references to the labs SSH config file added and removed during start up and tear down.

Jumphost

When the Sherpa server is running on a remote host, lab nodes can be accessed via SSH using the Sherpa server as a jumphost.

The sherpa ssh <node-name> command uses the generated sherpa_ssh_config file to jump to the lab nodes via the Sherpa server.

For ease of use, it is recommeded to copy your ssh keys to the Sherpa server to allow passwordless connectivity to remote nodes.

Tunneling

SSH tunneling allows for the connection of remote resources from your local machine by tunneling through SSH.

TODO: Add diagram showing SSH tunneling

For example, connecting to a HTTP server running on a lab-node.

# ssh -N -L {local-port}:{node-ipv4}:{node-port} {sherpa-server}

ssh -N -L 9443:172.31.0.11:443 lab01

You can now open a browser and from https://localhost:9443 access the web server on the lab node 172.31.0.11:443

Note

In a future release, SSH tunneling of service ports will be built into Sherpa.