dhclient not able to obtain an IP address from my isp's cable modem

JC Ferguson phish-jc at charter.net
Wed Oct 11 04:14:41 UTC 2006

Darn.  I thought I had a trace saved - I stuck the linux machine and my
winblows machine on a hub, gave my windows a static ip, then sniffed - had the
traffic from the linux -> out to the WAN in there and everything.  I used the
trace for debugging - I compared a good one from my winblows machine to the one
from linux, noticed the option list difference, changed dhclient.conf to tweak
the request to look like windows's request as much as possible to no avail.  If
I see it again, will capture and send.


"David W. Hankins" wrote:

> On Mon, Oct 09, 2006 at 11:56:40PM -0400, JC Ferguson wrote:
> > Well, I got it to go.  Lord knows how/why, but it now works.  I had 2x
> > 3COM cards, same vintage, in the box.  For the hell of it, I tried
> > removing one of them and replacing it with a cheapo one based on the good
> > old DEC TULIP chip.  This card was able to get a DHCP address w/o issue.
> A sniffed packet exchange (hard to get out of linux because the
> interface gets put 'down' so tcpdump exits...you have to manually
> ifconfig up and start tcpdump, then ifstart/dhclient manually) of
> the 'broken' case, and the lines dhclient emits at 'info' level to
> syslog at the same time would be helpful if you encounter this
> again.  Send the packet trace to dhcp-bugs at isc.org separately, the
> dhcp-users list strips binary attachments.
> --
> ISC Training!  October 16-20, 2006, in the San Francisco Bay Area,
> covering topics from DNS to DDNS & DHCP.  Email training at isc.org.
> --
> David W. Hankins        "If you don't do it right the first time,
> Software Engineer               you'll just have to do it again."
> Internet Systems Consortium, Inc.       -- Jack T. Hankins

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