Tnnl

Tnnl is a command-line utility for wrangling SSH tunnels.

Unlike most SSH tunnel utilities I've come across, Tnnl will not clutter your filesystem with a preferences YAML file. Instead it will try to make use of your native SSH config (at ~/.ssh/config for most folks).

This project is still in an early/alpha state. You have been warned. :)

Usage

Open an SSH tunnel

Open an SSH tunnel between local port 1234 and port 5678 on the remote host mysql.spatula.grommet. If local port 1234 is unavailable, Tnnl will increment by 1 until it finds an open port.

$ tnnl 1234:[email protected]:3306

You can omit the local port number, and Tnnl will try to use the same port for the local and remote hosts.

$ tnnl [email protected]:3306

If you have defined a host alias in your SSH config, you can save yourself some keystrokes by referencing that alias.

$ tnnl db:3306

Find and close open tunnels

Use tnnl list to list all open SSH tunnels that were created by Tnnl.

$ tnnl list
1. localhost:3307  ==>  mysql.spatula.grommet:3306
2. localhost:3000  ==>  123.45.67.89:3000
3. localhost:666   ==>  chunkybacon.gov:666

You can use the index numbers referenced in tnnl list to close 1 or more tunnels.

$ tnnl close 2
$ tnnl close 1 3

Or close all tunnels created by Tnnl.

$ tnnl close all

Known Issues

The list feature relies on renaming processes via $0, which does not work properly on Ruby 1.9.3-p0 on OS X. This appears to be an issue with this particular build of Ruby on this platform (https://groups.google.com/forum/#!topic/urug/zfmEGqjX47M). 1.9.3-p0 users on OS X are encouraged to upgrade to a newer build.
Tnnl uses Net::SSH under the hood, and Net::SSH currently supports only a subset of OpenSSH configuration options. The StrictHostKeyChecking preference is not supported, so Tnnl errs on the safe side and prompts you to update ~/.ssh/known_hosts when a modified host key is detected. Feel free to open an issue and/or submit a pull request if this is ruining your day.