LinuxQuestions.org - Network device (integrated Broadcom BCM4402) link down

Dear all,

Basic info:
* Ubuntu 8.10
* Dell Dimension 2400
* Network controller: Broadcom BCM4402 Integrated 10/100BaseT

I have been running this installation with a wired network connection with no problems whatsoever for about a week. Device eth0 appeared in the NetworkManager Applet, my network cable ran from my box to my functioning router, and I thought no more of it.

Yesterday, however, after booting, and also after every subsequent boot, I have not had any network devices available. This is presumably not a problem with my router or cable (in any case, both work fine with any other PC).

Hopefully you will forgive me in the following for not attaching logs etc as the machine has no connection to the net or my network whatsoever.

Running "cat /var/log/messages | grep eth0" returns: "Dec 9 16:53:02 james-desktop kernel: [ 9944.000080] b44: eth0: Link is down."

This line is very near the beginning of the log file. Running "cat /var/log/messages | top" returns:
Dec 9 15:14:54 james-desktop syslogd 1.5.0#2ubuntu6: restart.
Dec 9 15:29:07 james-desktop - - MARK - -
Dec 9 15:49:07 james-desktop - - MARK - -
Dec 9 16:09:07 james-desktop - - MARK - -
Dec 9 16:29:08 james-desktop - - MARK - -
Dec 9 16:49:08 james-desktop - - MARK - -
Dec 9 16:53:02 james-desktop kernel: [ 9944.000080] b44: eth0: Link is down.
Dec 9 16:16:21 james-desktop syslogd 1.5.0#2ubuntu6: restart.
[...]

I don't think you should get confused by the change in system time at restart here - I think I've already established that my system clock is screwed. I'll leave that for now.

Running "lspci | grep Network" returns:
01:09.0 Network controller: Broadcom Corporation BCM4402 Integrated 10/100BaseT (rev 01)

Running "sudo lshw" returns, among other things:
*-pci
description: PCI bridge
product: 82801 PCI Bridge
vendor: Intel Corporation
[...]
*-network
description: Network controller
product: BCM4402 Integrated 10/100BaseT
vendor: Broadcom Corporation
physical id: 9
bus info: pci@0000:01:09.0
version: 01
width: 32 bits
clock: 33 Mhz
capabilities: bus_master
configuration: driver=b44 latency=64 module=ssb
[...]
*-network DISABLED
description: Ethernet interface
physical id: 1
logical name: pan0
serial: 7a:04:e4:23:ef:c3
capabilities: ethernet physical
configuration: broadcast=yes driver=bridge driverversion=2.3 firmware=N/A link=yes multicast=yes

This last section is possibly the problem. I am not sure what exactly this "Ethernet interface" is, what pan0 means, why it has a MAC address (is it actually a physical piece of hardware separate to the integrated Broadcom?), etc. But the "network DISABLED" bit is the most worrying. I don't know what this means or how to get further information on it - google seems to draw a blank. The "NetworkManager Applet" in Ubuntu has "Enable Networking" checked, but I don't think that's related to this (?). I have tried to add the said MAC address to the list of wired connections in NetworkManager, but to no avail.

Running "sudo ifdown eth0" returns "interface eth0 not configured".

Running "sudo ifup eth0" returns "Ignoring unknown interface eth0=eth0".

Running "ifconfig" returns only the loopback interface - no eth0 mentioned.

I'm stuck now. Some people seem to be reporting problems with the b44 driver under heavy traffic (https://bugs.launchpad.net/ubuntu/+s...ux/+bug/279102) but my problem seems a bit more permanent.

My experience with linux is only as long as my week-long successful install configuration. Any help will be muchly appreciated.

James