Sniffing in Linux is simply a matter of enabling monitor mode on the wireless NIC and firing up Wireshark. Unfortunately, the procedure for enabling monitor mode differs with each model of wireless NIC, so I can’t offer a definitive guide for that here. In fact, some wireless NICs don’t require you to enable monitor mode. Your best bet is to do a quick Google search for your NIC model to determine how to enable it and if you need to do so.
One of the more common ways to enable monitor mode in Linux is through its built-in wireless extensions. You can access these wireless extensions with the
iwconfig command. If you type
iwconfig from the console, you should see results like this:
$ iwconfig Eth0 no wireless extensions ...