7 October 2008
A lot of distributions offer their own wireless management tools. While this can be helpful for a new user, an experienced GNU/Linux user knows that all these tools rely on the generic wireless extension offered by Wireless Tools for Linux.
Today I will show you how to manage your wireless connection by using a subset of the Wireless Tools (iwconfig, iwlist, and ifrename).
Note: I do not use wpa_supplicant.
Some required settings.
You need CONFIG_NET_RADIO=y in your kernel config (it creates /proc/net/wireless). Also, your results from this tutorial will improve with Wireless Tools version 27 and above. Use iwconfig –version to determine your version.
Make your interface consistent with ifrename.
ifrename allows you to assign a consistent name to each of your network interfaces. Normally, interface names are dynamic, meaning that each interface is assigned a name on a first detected, first assigned basis. Because each interface has some static elements, you can apply naming rules on them to provide a consistent name regardless of when the interface was detected.
Of course, you need to ascertain some information from each device before applying rules to them. The file to edit is /etc/iftab.
Entries in /etc/iftab consist of a set of mappings: interface name and descriptors. I find it easier to match devices based on their drivers. Example entries can be found in `man iftab`. I use:
b44 driver b44
iwl driver iwl3945
After you have finished editing /etc/iftab, add ifrename to your boot up scripts to automatically rename your devices. You’ll need to make sure that the command is issued before the devices are brought up. Use `ifrename -V -D` to see what would happen if you actually issued the command.
Managing the network.
iwconfig iwlist are your tools.
The first thing you usually do is search for available networks. `iwlist scanning` will show all the available networks.
Once you find a network, connect to it with iwconfig. iwconfig is your tool for configuring the wireless interface; it is normally used to connect to a network. Usage is simple, usually in the form: iwconfig <interface> <option> <parameters>. Typically you’ll be using the following:
iwconfig <interface> essid <ESSID>
iwconfig <interface> key <KEY>
That’s all there is too it. You can view your current authentication settings with `iwlist auth`.