dhclient doesn't respond to DHCP OFFER

From: seandarcy (seandarcy_at_hotmail.com)
Date: 10/06/03 

Date: Mon, 06 Oct 2003 20:48:42 GMT

I have a small old machine I'm setting up to route for my cable
connection with ool. It has two pcmcia nework cards - one connected to
the cable modem, the other to the local hub. Both cards work when
conected to the hub - i.e. other machines on the lan can connect to them.

But...neither card works when I try to run dhclient on the cable modem.
What's weird is that I moved another machine to the cable modem - also
redhat 9.0. It worked! dhclient quickly got the address.

On the first machine, I've flushed iptables, blanked out my hosts.deny,
and changed hosts.allow to ALL:ALL.

I got ethereal to look at what was happening. Here's a bunch of snips.

Almost all of the traffic was ARP requests from the Cisco router from
ool confirming the leases. Note my machine is getting back DHCP OFFER's
and DHCP ACK's (43,44,120,121,198,199 ) [ there's no DHCPDISCOVER before
the first ACK because ethereal started up a little late.] but dhclient
doesn't respond - it just keeps sending DHCPDISCOVER requests.

At the end Xircom, the adapter, asks if anybody's seen the gateway. It
then pings away, using the address the other machine ( the one that
worked ) uses. No response.

WTF is happening. ool seems to be be doing what it's supposed to. The
adapters are working - else how could ethereal see this stuff.
The firewall is flushed. Both the good machine and the bad machine are
using dhclient - 3.0p12. Both adapters on the bad machine have the same
problem. Both machines are using 2.4.22 kernel. The adapters on the bad
machine work fine on the LAN.

Any help reallly appreciated.

sean

     No. Time Source Destination
Protocol Info
       1 0.000000 Cisco_e3:81:56 Broadcast ARP
   Who has 24.44.12.158? Tell 24.44.8.1
       2 0.128525 Cisco_e3:81:56 Broadcast ARP
   Who has 24.44.10.242? Tell 24.44.8.1
       3 0.207890 Cisco_e3:81:56 Broadcast ARP
   Who has 67.86.253.152? Tell 67.86.240.1
.................

      43 5.515039 10.122.208.1 255.255.255.255 DHCP
   DHCP Offer - Transaction ID 0x1800
      44 5.684118 10.122.208.1 255.255.255.255 DHCP
   DHCP ACK - Transaction ID 0x1800

..............

      97 12.765007 0.0.0.0 255.255.255.255 DHCP
   DHCP Discover - Transaction ID 0x76db9156

............

     120 15.956841 10.122.208.1 255.255.255.255 DHCP
   DHCP Offer - Transaction ID 0xfffffba0
     121 16.049819 10.122.208.1 255.255.255.255 DHCP
   DHCP ACK - Transaction ID 0xfffffba0

.............

  198 27.228633 10.122.208.1 255.255.255.255 DHCP
DHCP Offer - Transaction ID 0xffffc490
     199 27.318397 10.122.208.1 255.255.255.255 DHCP
   DHCP ACK - Transaction ID 0xffffc490
     200 27.418549 Cisco_e3:81:56 Broadcast ARP
        DHCP Discover - Transaction ID 0x76db9156
...........................

     202 27.698475 0.0.0.0 255.255.255.255 DHCP
   DHCP Discover - Transaction ID 0x76db9156
..........................

     291 40.699363 0.0.0.0 255.255.255.255 DHCP
   DHCP Discover - Transaction ID 0x76db9156

........................

     405 56.120297 Xircom_37:6c:9e Broadcast ARP
   Who has 67.86.240.1? Tell 67.86.243.131

...............................

     416 57.119705 67.86.243.131 67.86.240.1 ICMP
   Echo (ping) request

...........................

     428 58.119779 67.86.243.131 67.86.240.1 ICMP
   Echo (ping) request

....................

     435 59.119946 67.86.243.131 67.86.240.1 ICMP
   Echo (ping) request

...................

     441 60.119855 67.86.243.131 67.86.240.1 ICMP
   Echo (ping) request
....................................
     446 61.119908 67.86.243.131 67.86.240.1 ICMP
   Echo (ping) request
..............................
     453 62.119980 67.86.243.131 67.86.240.1 ICMP
   Echo (ping) request
...............................
     460 63.120081 67.86.243.131 67.86.240.1 ICMP
   Echo (ping) request
..........................
     471 64.120133 67.86.243.131 67.86.240.1 ICMP
   Echo (ping) request
..................................
     479 65.120222 67.86.243.131 67.86.240.1 ICMP
   Echo (ping) request
.......................

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