Subject: Re: How to detect net cable plug-in
To: Jason Thorpe <>
From: Robert Elz <kre@munnari.OZ.AU>
List: tech-net
Date: 10/15/2003 03:40:32
    Date:        Mon, 13 Oct 2003 23:39:42 -0700
    From:        Jason Thorpe <>
    Message-ID:  <>

  | On Monday, October 13, 2003, at 10:42  PM, Brian Grayson (home) wrote:
  | >   Here's the problem:
  | >
  | >   - dhclient, when run on an ex0 interface, causes the link to go down
  | >     and then up again (ifi_link_state twiddles)
  | This is actually the real problem -- dhclient should not be causing the 
  | interface to reset in this manner.

It is almost certainly the driver, rather than dhclient.   dhclient does
nothing much to interfaces, it just causes ifconfig to get run (quite a
lot) - but some drivers like to reset the device whenever the address is
configured, or all kinds of other comparatively minor changes like that.

The ex driver is one of those that has this problem - I had a version of it
ages ago (which is probably lost now) where I avoided some of those resets.
It still seemed to work just fine.