autossh

Persistent SSH tunnels

Install

Using npm

npm i -S autossh

Usage

To Start

const autossh = require('autossh');

autossh({
  host: '111.22.333.444',
  username: 'root',
  localPort: 64444,
  remotePort: 5432
})
.on('error', err => {
  console.error('ERROR: ', err);
})
.on('connect', connection => {
  console.log('connected. Tunnel established on port ' + connection.localPort);
  console.log('pid: ' + connection.pid);
});

...is equivalent to...

ssh -NL 64444:localhost:5432 -o "ExitOnForwardFailure yes" root@111.22.333.444

Generate Dynamic Local Port

If you want to dynamically/randomly generate a port number, provide a string auto for the localPort.

Port conflicts will automatically be avoided and the generated port will not be in use.

See demo.js for an example.

Killing the Autossh Process

The autossh process will automatically die if the node process is closed, but you can manually kill the process using kill.

If you try to kill the ssh process from the command line while the node process is active, a new ssh tunnel will be established (which is the point of autossh). You will need to kill the node process first or call the kill method on the instance.

Example 1

const myAutossh = autossh({
  host: '111.22.333.444',
  username: 'root',
  localPort: 64444,
  remotePort: 5432
})
.on('connect', connection => {
  console.log('connected: ', connection);
});

myAutossh.kill();

Example 2

const myAutossh = autossh({
  host: '111.22.333.444',
  username: 'root',
  localPort: 64444,
  remotePort: 5432
})
.on('connect', connection => {
  console.log('connected: ', connection);
  connection.kill();
});