Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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I have a box that predominantly runs Ubuntu 9.04, though it does have Windows around as well (I've happily gotten to the point where I rarely load Windows). It has an integrated Ethernet card (a nvidia) on the motherboard (was eth0 though it is no longer enabled), as well as a separate one, an Intel(R) PRO/100 M Desktop Adapter, (eth1).
The integrated one no longer works at all, as the system was struck by lightning a few years ago. In Windows, for the sake of comparison, it is disabled so that the separate one (the Intel) is the only one ever detected. I have also tried disabling it in the BIOS, and this seemed to work well.
However, in Ubuntu, I'd say 40-50% of the time, when I boot the system it says the eth1 card is disconnected. If I restart, it usually connects properly, though sometimes it takes two restarts.
My original thought was that Ubuntu must be detecting the card that no longer works, but this does not seem to be the case.
When it is not working, it still detects the right card, but I cannot seem to do anything to get it to connect, aside from rebooting.
What kind of things can I do to figure out what the issue might be, and how to fix it?
This probably relates to the latest udev persistent rules which has been sneaked in and is, in my opinion, a pain in the rear end.
Take a look at /etc/udev/rules.d/70-persistent-net.rules and see if the card is being listed there.
I have been having similar problems with a server continually not bringing up a connection because of this. I found that when this happens using ifconfig -a will show all the devices available and invariably it has changed the eth numbering. This means either editing the rule file or editing the /etc/network/interfaces file.
There may be a possible solution based on the theory of how this is supposed to work;
udev is supposed to identify the card by the mac code. Now you can edit the identity by changing the name of the device in the 70-persistent-net.rules by for example changing NAME = "broken_nvidia".
I would also suggest trying to fool the system by adding a dummy entry in your interfaces file on a different subnet address like;
iface broken_nvidia inet static
So in theory if the system does locate this card it knows its name and can relate a network entry for it and therefore not interfere with the other device. Since it is a dummy connection it doesn't matter whether the device works or not.
That seems to have had an effect, at least. Now, when it seems like it would ordinarily be a use case where there is no connection, the system indicates that it is connected, but it can't connect to anything.
In case it is relevant, some of the output for the commands I ran initially is different:
sudo ifup eth1:
ifup: interface eth1 already configured
dmesg | grep -i eth:
[ 1.069444] Driver 'sd' needs updating - please use bus_type methods
[ 1.069451] Driver 'sr' needs updating - please use bus_type methods
[ 3.183340] e100: eth0: e100_probe: addr 0xe7021000, irq 10, MAC addr 00:0e:0c:66:64:04
[ 10.447693] udev: renamed network interface eth0 to eth1
[ 24.632979] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[ 32.032536] ADDRCONF(NETDEV_UP): eth1: link is not ready
[ 32.036228] e100: eth1: e100_watchdog: link up, 100Mbps, full-duplex
[ 32.046512] ADDRCONF(NETDEV_CHANGE): eth1: link becomes ready
[ 42.512017] eth1: no IPv6 routers present
[ 53.816312] e100: eth1: e100_watchdog: link down
[ 55.816227] e100: eth1: e100_watchdog: link up, 100Mbps, full-duplex
[ 59.816306] e100: eth1: e100_watchdog: link down
[ 61.816221] e100: eth1: e100_watchdog: link up, 100Mbps, full-duplex