freebsd stable - May 2006 - bogus dhclient EXPIRE when using wi0

Using 6.1-STABLE cvsup'd on 5/9, I am noticing that on insertion
of a wi0 card, dhclient is invoking its dhclient-script several
times, as follows, from instrumentation added to the script:

Sun May 14 18:34:20 EDT 2006 dhclient reason=PREINIT
Sun May 14 18:34:20 EDT 2006 dhclient reason=REBOOT
Sun May 14 18:34:21 EDT 2006 dhclient reason=EXPIRE

The third invocation, the EXPIRE, is wrong.  This EXPIRE has the
effect of causing the just-acquired IP address to be deleted, so
the i/f appears to have no IP address.

Interestingly, if dhclient is run manually, immediately following
this, as in:
	# killall dhclient
	# dhclient wi0
the dhclient-script invocations then do not include the EXPIRE, as
one would expect:

Sun May 14 18:36:49 EDT 2006 dhclient reason=PREINIT
Sun May 14 18:36:50 EDT 2006 dhclient reason=REBOOT

Further instrumentation of the dhclient-script shows that the
EXPIRE does seem to be premature, in that the value of $old_expiry
does appear to be (well) beyond the current time.

Anyone have thoughts on why this is happening?

Tcpdumping the DHCP dialog on shows a perfectly normal exchange
with the server, by the way.

	-jr

On Sun, May 14, 2006 at 06:48:16PM -0400, J.R. Oldroyd
wrote:
> Using 6.1-STABLE cvsup'd on 5/9, I am noticing that on insertion
> of a wi0 card, dhclient is invoking its dhclient-script several
> times, as follows, from instrumentation added to the script:
> 
> Sun May 14 18:34:20 EDT 2006 dhclient reason=PREINIT
> Sun May 14 18:34:20 EDT 2006 dhclient reason=REBOOT
> Sun May 14 18:34:21 EDT 2006 dhclient reason=EXPIRE
> 
> The third invocation, the EXPIRE, is wrong.  This EXPIRE has the
> effect of causing the just-acquired IP address to be deleted, so
> the i/f appears to have no IP address.
> 
> ...
> Further instrumentation of the dhclient-script shows that the
> EXPIRE does seem to be premature, in that the value of $old_expiry
> does appear to be (well) beyond the current time.
> 
> Anyone have thoughts on why this is happening?
I've seen it occasionally.

I have been using a dhclient-exit-hooks script anyway (to set hostname,
try to synch with an NTP server, and set firewall rules), so I modified
my dhclient-exit-hooks script to just (log and) ignore EXPIRE requests.

That could be wrong or anti-social, but then again, my laptop rarely
goes more than 18 hours at a strech -- I track RELENG_6 & HEAD on it
every day there's been a change in the (respective) sources....  :-}

Peace,
david
-- 
David H. Wolfskill				david@catwhisker.org
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