Re: DHCP timeout patch

[Peter Jones <pjones redhat com>]

On Wed, 2006-03-22 at 10:27 -0500, Robert Love wrote:
> On Thu, 2006-03-16 at 16:09 +0100, Radek Vok�wrote:
> > Hi, I've realized that 25sec DHCP timeout limit is not enough on my slow
> > network, so I've proposed a small patch on RH bugzilla for adding new
> > option to NetworkManager, allowing to specify the timeout value.
> > 
> > Please see https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=185611
> 
> I would prefer that we just set the timeout to a sensible value by
> default and leave it at that -- making it configurable seems a bit much,
> particularly at compile-time.

Well, the real solution, at least for a great many of the "dhcp times
out too soon" cases, is is to have something listening in promiscuous
mode on wired networks, to see if we see certain types of packets.
Specifically, BPDU packets for Spanning Tree.  If we see packets
inquiring as to our status as a bridging switch, we need to increase the
timeout.

But that's a PITA, because it needs to inform NM, dhclient, possibly
_shell scripts_ that dhclient runs, etc.  And it's not only a problem
for NM -- eventually we need to do something like this in e.g. RH's
installer, as well.

I've written the code to listen before, so could probably reproduce that
part pretty quickly, but actually integrating it sanely is a lot of
work.

-- 
  Peter