Subject: Re: dhclient/dhcp and dynamically-inserted interfaces?
To: Manuel Bouyer <bouyer@antioche.lip6.fr>
From: None <dme@dme.org>
List: tech-net
Date: 09/30/2000 20:10:11
* bouyer@antioche.lip6.fr [2000-09-30 16:19:38]
| > Here's a question: Say I pop a pc-card into a laptop running
| > NetBSD (1.5-ALPHA2 or -current).  If dhclient dhclient [or dhcp] is
| > already running, will it notice the new interface and solicit [or
| > respond] for an IP address?
| 
| Hum, there's a '-w' flag that may do what you want, but it's not
| clear that it's going to find the new interface by itself.

-w may provide some of the solution, but it's not enough.  In
particular, if dhclient starts when there are no interfaces present it
does `the wrong thing' (i.e. nothing).

| The man page mention a dhcpccp program that could be used to notify
| dhclient that an interface has been added or removed, but it seems
| it's not installed on NetBSD, and I didn't find it in the 1.5
| sources :(

I filed a PR for this a few days ago.  The program doesn't exist in
the current sources from ISC either.

Given that there is support for detecting USB insertion events (I have
USB ethernet at the office and pcmcia at home), I guess we should
build some user-space code that monitors the various possible sources
of dynamically-added devices (not just net) and performs
user-specified actions.  Has anyone looked at this yet ?

dme.