Here's a very vexing problem.

I recently installed Debian on a laptop using a live CD. Now with the same NIC and ethernet connection, I can't get a DHCP offer. I'm running Windows machines off the same cable modem no problem.

I've looked at many FAQs, HOWTOs and forums but cannot seem to resolve this issue. ifconfig reveals eth0, which appears to be functioning normally (it's plugged in).

Using ifdown eth0 and then ifup eth0, I get a series of DHCPDISCOVERs but no DHCPOFFERs. Resetting the cable modem and restarting the computer does not resolve this issue. All the while, my Windows machines work fine.

I suspect it's not a hardware issue since I used the same NIC and ethernet connection to install Debian in the first place. I'd be more than grateful for any advice on how to troubleshoot this issue and can provide the syslog entries if that would help.

what are the contents of your /etc/network/interfaces file?

Perhaps we could get you to post the output of the following commands:

ethtool ethX

where X is the number of the interface you are using.

ifconfig


This information will give us something to go on.

Regards,

Fordeck

Thanks much - will post results from ethtool and ifconfig a bit later.

etc/network/interfaces doesn't have anything fishy...as I recall:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp

try using pump to force the interface into a dhcp request:

apt-get install pump
pump -i eth0

hopefully thatll get you some kind of results...

Perhaps we could get you to post the output of the following commands:

ethtool ethX

where X is the number of the interface you are using.

HMMM...I DON'T HAVE ETHTOOL ON MY SYSTEM THAT I KNOW OF

ifconfig

HERE'S WHAT IFCONFIG HAS TO SAY:

eth0

Link encap: Ethernet HWaddr 00:0b:db:02:0a:0d
UP BROADCAST MULTICAST MTU: 1500 Metric: 1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collissions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:11 Base address:0x6c00

eth1

Link encap: Ethernet HWaddr 00:02:2d:86:ec:ec
inet6 addr: fe80::202:2dff:fe86:ecec/64 Scope:Link
UP BROADCAST MULTICAST MTU: 1500 Metric: 1
RX packets:447 errors:0 dropped:0 overruns:0 frame:0
TX packets:70 errors:32 dropped:0 overruns:0 carrier:0
collissions:0 txqueuelen:1000
RX bytes:73195 (61.4 KiB) TX bytes:22766 (22.2 KiB)
Interrupt:5 Base address:0xe100

eth0:avahi

Link encap: Ethernet HWaddr 00:0b:db:02:0a:0d
inet addr: 169.254.2.49 Bcast:169.254.255.255 Mask: 255.255.0.0
UP BROADCAST MULTICAST MTU: 1500 Metric: 1
Interrupt:11 Base address:0x6c00

lo

Link encap: Local Loopback
inet addr: 127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU: 16436 Metric: 1
RX packets:72 errors:0 dropped:0 overruns:0 frame:0
TX packets:72 errors:0 dropped:0 overruns:0 carrier:0
collissions:0 txqueuelen:0
RX bytes:6270 (6.1 KiB) TX bytes:6270 (6.1 KiB)

THANKS

Have you tried using dhclient? You could run the following command:

dhclient ethX

where X is the number of the interface you are using. That command will get your machine to try again for a DHCP address. If your not running as root you may need to preface it with 'sudo'.

You might also try running:

mii-tool ethX

This will show your link status. Again these commands need to be ran as the user root.

Regards,

Fordeck

dhclient eth0 resulted in the same thing I'd seen before using ifup eth0...

DHCPDISCOVER on 255.255.255.255 port 67 interval X
blah
blah
blah

No DHCPOFFERS...



mii-tool says there's no link

I checked cat syslog.1 | grep eth0 and found that it says eth0 is fully supported...

The device is:

Ethernet controller: 3Com Corporation 3c905C-TX/TX-M [Tornado] (rev 78)

I plugged in the ethernet cable to my windows machine and got online no problem.

Any other thoughts on what could be causing this problem? Again, I had no problem installing Debian from the live CD using the same connection...

Thanks again.

Intriguing...

I just got it to work by switching to a lower runlevel!

Now it seems to work fine in all runlevels, though I'm not sure if that was something to do with my computer or perhaps my finicky ISP...

Anyway, thanks everyone for your suggestions. Be interested to hear thoughts on what could have been going on...

Here's a thought -

I checked the interrupts file and noticed that a bunch of things were assigned to interrupt 11. Here's what the line says:

uhci_hcd:usb1, yenta, yenta, eth0, radeon@pci:0000:01:00.0

Any thoughts if this could have been causing the problem? If so, how would I resolve? Thanks.