5.3 + dhclient: bpf needed in kernel config?

[Robert Watson]

On Mon, 1 Nov 2004, Rob wrote:

> Aha. So I added bpf to my kernel config, recompiled and installed
> everything again. 
> 
> Yesterday this PC has been upgraded from 4.10 to most recent 5.3. I have
> in /etc/rc.conf
> 
>     ifconfig_rl0="DHCP" 
> 
> which worked jsut fine with 4.10, but seems to misserably fail with 5.3. 
> 
> Dhclient binds rl0 to 192.168.1.22 all the time, which seems to be a
> kind of default for a failing dhclient. 
> 
> Is something else, unusual, needed in 5.3, that is critical to dhclient? 

Other than BPF and, of course, INET, I don't know of specific other
dependencies.  I would suggest hooking up tcpdump to the interface before
running dhclient, and using a command something like the following:

    tcpdump -p -i rl0 udp port dhcpc or udp port dhcps &

And see what packets go out while dhclient runs.  BTW, dhclient gets
somewhat confused if run more than once, so I might do a "killall
dhclient" before experimenting to be on the safe side.  If it was
upgraded, you might try deleting the old leases database
(/var/db/dhclient.leases). 

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert at fledge.watson.org      Principal Research Scientist, McAfee Research