Arch Linux

jwm-art

Member

Registered: 2011-02-01

Posts: 87

Occasional problem with eth0 link down after booting

Hi,

Every so often after booting up the PC there is not any working network connection. Looking through the output of dmesg, I find "eth0 link down" messages. Not knowing a lot about networking lead me to resort to rebooting to resolve the problem, and rebooting does indeed resolve the problem. Today I discovered the post at  [url http://bbs.archlinux.org/viewtopic.php?id=117728] which suggests similar behaviour.

I played around with ifconfig and initially thought I was seeing the same behaviour, but believe I was mistaken. I can't actually confirm until it happens if my new found knowledge will actually resolve the problem without rebooting.

I'd like to try and track down the source of the problem, and either file a bug report or take some other (configuration) measure, but need help tracing it.

Hardware in question is: Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 01)
and I'm using the testing repository in Arch. Any help appreciated.

Cheers,
James.

hexanol

Member

From: Canaduh

Registered: 2009-08-04

Posts: 95

Re: Occasional problem with eth0 link down after booting

I have the exact same problem and I have the exact same ethernet controller/chip.

I've not looked that much why it was doing this. Maybe auto-negotiation fail for I don't know which reason, maybe something else, hard to tell. I might try to investigate this a bit more next time it does me this.

That said, what I'm doing when I'm seeing that my eth0 has no carrier, I'm doing a "ip link set eth0 down", wait a few seconds, and then a "ip link set eth0 up", and then it's usually fine. Since I'm personally using static IP addresses, I also have to re-add the default route after that, i.e. a "ip route add default via 192.168.1.1" to be able to go out of my LAN again. This will be different if you are using DHCP.