tunnelmon -- Monitor and manage autoSSH tunnels
================================================

## SYNOPSIS

`tunnelmon` [-h]

`tunnelmon` [-c] [-n] [-u] [-l LEVEL] [-g FILE]


## DESCRIPTION

`tunnelmon` is an autossh tunnel monitor. It gives a user interface to monitor existing SSH tunnel that are managed with autossh. 

It can print the current state of your tunnels or display them in an interactive text-based interface.

`tunnelmon` is released under the GNU Public License v3.


## INSTALLATION

`tunnelmon` targets Linux operating systems, and depends on:
* `openssh-client`
* `python` version 3.8 at least.

You may also want to install the recommend packages:
* `autossh`


## OPTIONS

Called without option,`tunnelmon` will print the current state of the autossh tunnels and exit.

* `-h`, `--help`:
  Show a help message and exit

* `-c`, `--curses`:
  Start the interactive user interface. Tunnels states will be updated regularly and you will be able to control them (see below).

* `-n`, `--connections`:
  Display only SSH connections related to a tunnel.

* `-u`, `--tunnels`:
  Only display the list of tunnels processes.

* `-l LEVEL`, `--log-level LEVEL`:
  Control the verbosity of the logging, the greater, the more verbose. Available log levels are: `error` < `warning` <
  `debug`. Defaults to `error`, which only prints unrecoverable problems.

* `-g FILE`, `--log-file FILE`:
  Log messages are written to the given FILE. Useful to debug the interactive interface.
  If not set, asking for the curses interface automatically set logging to the "tunnelmon.log" file.


## INTERACTIVE INTERFACE

Keyboard commands:

* `↑` and `↓`: Select a tunnel.
* `R`: Reload the selected autossh instance (i.e. send a `SIGUSR1`, which is interpreted as a reload command by autossh).
* `C`: Close the selected tunnel (i.e. send a `SIGTERM`).
* `N`: Show the network connections related to each tunnel instances.
* `Q`: Quit tunnelmon.


## SSH Tunnels in a nutshell

To open a tunnel to port 1234 of `server` through a `host` reached on port 4567:
```sh
ssh -N host -L4567:server:1234
```
You may add `-f` to run ssh in the background.

Autossh can restart tunnels for you, in case they crash:
```
autossh -f host -L4567:server:1234
```