Help creating bpf0 device (bpf won't do it for me)

Michael Powell nightrecon at
Sat May 9 20:22:45 UTC 2009

D C wrote:

> Hello,
> I'm in the final stages of setting up a new wireless connection but have
> been having problems getting bpf running.  For some reason, even though
> bpf has been compiled into a new kernel, the system won't automatically
> create a
> bpf0 device.  On boot, the system complains "pcap_open_live: (no devices
> found) /dev/bpf0: No such file or directory".
> The ultimate goal is to have this laptop connect wirelessly to my
> WPA2-protected WAP (already working fine with other boxes) using a static
> IP.
> I've successfully compiled in support for the Atheros-based PCMCIA card,
> edited rc.conf to exclude DHCP and to use wpa_supplicant.conf, and
> eventually compiled in bpf when I started receiving the pcap_open_live
> messages.
> I suspect bpf is needed not for DHCP which is not running, but for some of
> the parameters I added to wpa_supplicant.conf, which is as follows:

I confess to not having much knowledge in this area, but am interested
from considering adding a card to my gateway-firewall-router box.

I have two servers here at home, one is the afore mentioned gateway and
the other is an Apache/MySQL/Samba server. Looking at the /dev on both I
noticed that the gateway box has the bpf entries while the web server box
does not. So I believe there needs to be an interface such as a firewall
or DHCP which will consume the bpf in order for the /dev entry to be

I suspect that you may have skipped over the proper creation of your
wireless interface which would have created the bpf when initialized.

You may consider trying to get the interface up and running with wireless
connectivity without WEP/WPA first, then work on adding in the supplicant
afterwards. My belief is when the network interface for the card comes up
you will automagically then have the bpf entries in /dev.

You may also take a look at /etc/devd.conf and /etc/defaults/pccard.conf
for brain-jogging ideas. I do confess to not knowing enough about them.


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