+ You can capture raw 802.11 packets with AR5K cards on Linux systems
+ with the v5_ar5k drivers. You will need the Linux wireless-tools
+ version 25 or higher to put the card into monitor mode. It might also
+ be possible to do so with the madwifi driver. If you have information
+ on how to do this, please supply it to us, so that we can incorporate
+ that information into the FAQ in the future.
+
+ Other cards:
+
+ It might be possible to capture in monitor mode on other cards. If so,
+ please supply us with information on how to do so, so that we can
+ incorporate that information into this FAQ in the future.
+
+ Q 5.39: How do I capture on an 802.11 device in monitor mode on
+ FreeBSD?
+
+ A: On FreeBSD 5.2 and later, you should be able to capture in monitor
+ mode on 802.11 interfaces supported by the wi and acx drivers, if
+ Ethereal is linked with libpcap 0.8.1 or later, and on 802.11
+ interfaces supported by the an driver, if Ethereal is linked with
+ libpcap 0.7.1 or later.
+
+ For cards supported by the wi and acx drivers, you should:
+ 1. Put the card into monitor mode with the command ifconfig interface
+ monitor. You can also set the channel to monitor by adding the
+ argument channel channel_number to that command.
+ 2. When you start the capture, in Ethereal select "802.11" as the
+ "Link-layer header type", and in Tethereal add the command-line
+ argument -y 802.11.
+ 3. When the capture completes, turn off monitor mode with the command
+ ifconfig interface -monitor.
+
+ For cards supported by the an driver, you should:
+ 1. Put the card into monitor mode with the command ancontrol -i
+ interface -M flag, where flag should be the sum of:
+ + 1, to turn monitor mode on;
+ + 2, if you want to capture traffic from any BSS rather than
+ just the BSS with which the card is associated;
+ + 4, if you want to see beacon packets (capturing beacon
+ packets increases the CPU requirements of capturing).
+ 2. When the capture completes, turn off monitor mode with the command
+ ancontrol -i interface -M 0.
+
+ Don't add 8 in to flag; Ethereal currently doesn't support the full
+ Aironet header.
+
+ On FreeBSD 4.6 through 5.1, you should be able to capture in monitor
+ mode on 802.11 interfaces supported by the an driver, but not on any
+ other interfaces; see the instructions for FreeBSD 5.2 or later for
+ those cards.
+
+ In FreeBSD 4.5 and earlier, you will not be able to capture in monitor
+ mode on 802.11 interfaces (no drivers supported it prior to 4.5, and
+ in 4.5 the an driver had bugs that caused packets not to be captured
+ correctly).
+
+ Q 5.40: How do I capture on an 802.11 device in monitor mode on
+ NetBSD?
+
+ A: On NetBSD 2.0-beta and later, you should be able to capture in
+ monitor mode on 802.11 interfaces supported by the wi and acx drivers,
+ if Ethereal is linked with libpcap 0.8.1 or later. The instructions
+ are the same as for FreeBSD 5.2 and later.
+
+ Q 5.41: I'm trying to capture 802.11 traffic on Windows; why am I not