eth0 not connected but still receiving an address

BrummieJim · l33t Joined: 22 Jul 2005 Posts: 683

Hi,
Something's screwing up my network settings trying to start eth0 when no cable is connected and I use wireless (eth1). This means that I need a restart or a /etc/init.d/net.eth1 restart to get networking up. After booting my system looks like this;

Hawaiian ja # /sbin/route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
loopback * 255.0.0.0 U 0 0 0 lo
Hawaiian ja # ifconfig
eth0 Link encap:Ethernet HWaddr 00:C0:9F:78:85:61
inet addr:169.254.140.178 Bcast:169.254.255.255 Mask:255.255.0.0
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
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:6

eth1 Link encap:Ethernet HWaddr 00:0E:35:82:F5:EB
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1 errors:0 dropped:0 overruns:0 frame:0
TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3762 (3.6 Kb) TX bytes:7944 (7.7 Kb)
Interrupt:10 Base address:0xe000 Memory:d0214000-d0214fff

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:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)

Does anyone have any ideas why this might be happening? If you need any more information, just ask!

Cheers

desultory · Bodhisattva Joined: 04 Nov 2005 Posts: 9410

It is because there is no DHCP service available on that link, the interface is assigned an address from a reserved pool to allow basic network functionality to be preserved in such an environment.

BrummieJim · l33t Joined: 22 Jul 2005 Posts: 683

This never used to happen and seems to be screwing up my wireless. How can I stop it doing this?

Dagger · Retired Dev Joined: 11 Jun 2003 Posts: 765 Location: UK

edit /etc/conf.d/net

and set it as

BrummieJim · l33t Joined: 22 Jul 2005 Posts: 683

I presume this will stop eth0 working completely, unless I re-enable it. All I want is to go back to how it was before recent updates. If eth0 isn't there, it leaves it alone and brings up my wireless, else it uses eth0.

Ehnvis · Guru Joined: 13 Jun 2006 Posts: 305 Location: /dev/random

i would suggest you to emerge netplug, and your problem should go away. Netplug will take care of your eth0 and if there is a cable it will bring it up otherwise it will keep it down.
_________________
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Running Gentoo-2.6.21-r4 (again as 2.6.22 kernels hogs CPU), all but SD reader works fine.

BrummieJim · l33t Joined: 22 Jul 2005 Posts: 683

I've installed it, and I'll see how it goes, but why has this change happened and is there a place I should be looking for these changes?

BrummieJim · l33t Joined: 22 Jul 2005 Posts: 683

Seems to be working better but I still needed to run dhcpcd -d eth1 to get my wireless network on-line. Any ideas why this isn't running automatically?

serial_penguin · Posted: Tue Oct 09, 2007 3:38 am Post subject:

I had similar problems with dhcpcd 3.1.5. The 169.254.xxx.xxx ip address could be removed by passing the -L option to dhcpcd in /etc/conf.d/net. However, if I connected via my wired interface then subsequent wireless connections would be messed up. ifconfig would indicate two connections, one to the wired interface (which now wasn't connected) and one to the wireless interface. I would have to manually take down the wired interfaced so the wireless one would function. I could find no option to turn this off! I have downgraded to dhcpcd 3.0.16-r1 and things are back to normal. Also, I have never been able to get netplugd to play well with both my wired and wireless interfaces.

BrummieJim · l33t Joined: 22 Jul 2005 Posts: 683

Fantastic, I'll give that a go!

BrummieJim · l33t Joined: 22 Jul 2005 Posts: 683

No, downgrading dhcpcd hasn't worked either. Any ideas

serial_penguin · Posted: Wed Oct 10, 2007 2:37 pm Post subject:

BrummieJim · l33t Joined: 22 Jul 2005 Posts: 683

Hi,
Yes, I uninstalled netplug, but after downgrading it seems that the wireless is much more stable. From looking at the logs it looks as if dhcpcd just isn't starting on eth1 even though it starts on eth0, until I do it manually.

Corona688 · Veteran Joined: 10 Jan 2004 Posts: 1204

You can prevent dhcpcd from giving itself that obnoxious useless 169.x.y.z address with

serial_penguin · Posted: Fri Oct 12, 2007 5:26 am Post subject:

Well, it's nice to know I wasn't the only one bitten by this dhcpcd upgrade. I don't know if Corona688's script fixed BrummieJim's issues, but it fixed mine with the exception that now dhcpcd complains at boot about there being no cache info on the offending interface. Now perhaps the real issue is whether one should really have to go to these efforts to have a functioning ethernet interface after an upgrade? Hopefully, a developer will have some insight here.

ahocevar · Posted: Mon Oct 15, 2007 9:37 pm Post subject: Possible solution

* Messages for package net-misc/dhcpcd-3.1.6-r1:

* You have installed dhcpcd with DUID support.
* Some DHCP server implementations require a MAC address only in the
* ClientID field. These DHCP servers should be updated to be RFC
* conformant. If you cannot do this, you can revert to the old
* behaviour by using the -I '' option OR building dhcpcd with the
* vram USE flag enabled.

For me, it worked to add