OpenWrt Forum Archive

Topic: Tcpdump cannot capture

The content of this topic has been archived on 6 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

Hi,

I've did vanilla build

a) libpcap-1.1.1
b) tcpdump-4.2.1 (static)

on Attitude adjustment and when running tcpdump I get

root@OpenWrt:~# ./tcpdump -i mon0
tcpdump: live packet capture not supported on this system


Interface mon0 I've got from

iw phy phy0 interface add mon0 type monitor
ifconfig mon0 up

Does anyone knows what could be source of the problem?

Tnx,
vnv.

I use existing packages and it works fine (on Barrier Breaker):

opkg update
opkg install tcpdump

/usr/sbin/iw phy phy0 interface add moni0 type monitor
/sbin/ifconfig moni0 up
/usr/sbin/tcpdump -i moni0

Furthermore check if your wlan interface supports monitor mode ("Supported interface modes")

iw list

(Last edited by bluepuma on 11 Mar 2014, 15:02)

Hey bluepuma,

when I install it with opkg it also works, but I would to to make changes to tcpdump and need to build it from source.

Are there some specific patches to it to be aware of?

N.

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