Call script after connecting to a wireless network

Is there a way for me to call a shell script once I connect to a specific wireless network? Reason I want to do this is I have to login to the network before I can start using it and I would like to automate this if possible.

I read this question: Is there a way to run a script every time I connect to a specifc wireless network?

But I'm really unsure as to how to use upstart to do it.

Solution 1:

Apologies for my previous answer which was the way I would have done it years ago. Seems things have changed.

It turns out that Network Manager runs ALL of the scripts in the /etc/NetworkManager/dispatcher.d/ directory (those owned by root, that are executable, that are not readable by other users, and not setuid), when a connection changes (up, down, preup, predown).

Environment variables are set and passed to this script by Network manager. You'll be interested in the CONNECTION_UUID environment variable (contains a unique string).

So, to solve your problem (execute a script when a particular wireless network is connected to):

1) find out the uuid of the wireless connection you're interested in (by looking inside the appropriate connection file in the /etc/NetworkManager/system-connections/ directory).

2) write a bash (or perl, or python, or whatever) script that does what you want if the environment variable CONNECTION_UUID is a match to the uuid of the wireless network in (1) above.

3) put this script into /etc/NetworkManager/dispatcher.d/ and set the owner and permissions appropriately.

further reading: man networkmanager ( and a litte poking around the scripts in the directories mentioned above).

An example script:

#!/bin/bash
#####################################
# MounterBeast Script
# /etc/NetworkManager/dispatcher.d/02remotemount
# Copyright 2011 Nathan E. Williams
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Usage:
# This script must be customized for your configuration.
# By default, the script will attempt to mount a CIFS share
# when a specified MAC address is found at the network gateway,
# or over sshfs if the MAC address of the gateway is not the specified MAC.
# e.g. I mount over CIFS to the servers internal IP when at home, and
# over sshfs when away from home.
#
# id gateway mac without physically checking the sticker:
# $ arp -n -a $(ip route show 0.0.0.0/0 | awk '{print $3}') | awk '{print $4}'
#
# Testing:
# up) sudo /etc/NetworkManager/dispatcher.d/02remotemount wlan0 up
# down) sudo /etc/NetworkManager/dispatcher.d/02remotemount wlan0 down
#####################################
#
# Configuration:
#
targetmac='xx:xx:xx:xx:xx:xx'
mount_user='$USER'
mount_pass='pass'
internal_server_name='192.168.1.102'
external_server_name='my.dyndns.com'
share_name="music"
mount_point='/mnt/remote'
ssh_port='22'
#
# Should not need to edit below
#
gateway=$(ip route show 0.0.0.0/0 | awk '{print $3}')
mactest=$(arp -n -a $gateway | awk '{print $4}')

if [[ "$mactest" == "$targetmac" ]]
then
  case "$2" in
          up)
          sleep 5
          mount -t cifs -o username=$mount_user,password=$mount_pass //$internal_server_name/$share_name $mount_point
          ;;
          down)
          umount -l $mount_point
          ;;
  esac
else
  case "$2" in
      up)
          sleep 5
          sshfs -p $ssh_port $external_server_name:$share_name $mount_point
      ;;
      down)
          umount -l $mount_point
      ;;
  esac
fi

exit $?

Solution 2:

I don't know if there is a way to do it with Network Manager, there is one probably but I have another solution for you. You can install Wicd :

sudo apt-get install wicd

Wicd have support directly on the gtk interface to add pre-script and post-script support to every network you can connect. Take care that Wicd will desinstall Network-Manager to work (they are both in conflict) so if something goes wrong you should download the .deb of Network-Manager or have a Live-CD/Live-USB with you.

Wicd is easy to use and quicker to connect but lack some advanced features of Network-Manager (like VPN). Here is a screenshot :

Solution 3:

Yes, Shell scripts in /etc/NetworkManager/dispatcher.d/ for NetworkManager is a very good idea.

There is also a Dbus method with NetworkManager, more fun, more complicated: man nm-settings.

A resume of shells arguments from Man page of NetworkManager about dispatcher:

Each script receives two arguments, the first being the interface name of the device just activated, and second an action.

Action can be: up, down, vpn-up, vpn-down, hostname, dhcp4-change, dhcp6-change . (Release of the man page: 17 January 2012)

Here is a very simple script to restart OpenVPN after an network interface was up:

if [ "$2" = "up" ]; then  
       /etc/init.d/openvpn restart  
fi  
exit $?