[arch-general] Ethernet stopped working after update

[dmbuce at gmail.com]

On 06/26/2011 02:50 PM, Javier Vasquez wrote:
> On Sun, Jun 26, 2011 at 1:05 PM,<dmbuce at gmail.com>  wrote:
>> My card:
>>
>> # lspci | grep -i ethernet
>> Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI
>> Express Gigabit Ethernet controller (rev 03)
>>
>> After doing pacman -Syu, ethernet on my desktop stopped working. The card on
>> my laptop is the same, at least according to lspci, and is working fine.
>>
>> When I upgraded, there was a change in syntax in rc.conf for defining the
>> network, but I'm just attempting dhcp for now before I try to set up a
>> static ip:
>>
>> interface=eth0
>> address=
>> netmask=
>> gateway=
>>
>>
>> I've tried resetting the router and switching from the kernel's r8169 driver
>> to the r8168 driver from the aur. I compiled the aur driver on my laptop and
>> transferred to the desktop on usb -- as long as they're both x86_64, this
>> shouldn't be a problem, right?
>>
>> Regardless of my choice of driver, ethernet on the laptop works fine, and
>> doesn't work at all on the desktop. If I set up ethernet manually using
>> ifconfig to define the address/netmask/broadcast/etc (making sure the routes
>> are correct), everything appears to work fine until I try to ping the router
>> and get "Destination Host Unreachable".
>>
>> And the kicker is that the light on the router for the port I have my
>> ethernet cable plugged into will light up for the laptop, but not the
>> desktop. Given this and the other behavior, I'm inclined to think it's a
>> hardware issue, but this hardware is only several months old, and having
>> this happen right after an upgrade seems unlikely to be a coincidence.
>> Anything else I can try short of reinstalling or getting a replacement from
>> the manufacturer?
>
>
> I'm using netcfg, and haven't found problems so far with all
> changes...  The daemon is net-profiles, and you can copy the example
> for static wired profile into a valid profile, and setup rc.conf
> accordingly.
>
> See:
>
> https://wiki.archlinux.org/index.php/Netcfg
>
>

How odd. Every other method I've tried for setting up a static IP 
succeeds (but doesn't actually get me a working connection). Netcfg 
gives me this:

root at bender:~# cat /etc/network.d/ethernet
CONNECTION='ethernet'
DESCRIPTION='Ethernet'
INTERFACE='eth0'
IP='static'
ADDR='192.168.0.120'
GATEWAY='192.168.0.1'
DNS=('192.168.0.1')
root at bender:~# netcfg ethernet
:: ethernet up 
  [BUSY]
  > No connection
 
   [FAIL]
root at bender:~#


Doing 'sh -x netcfg ethernet' shows that it's printing 'No connection' 
from '/usr/lib/network/connections/ethernet up ethernet' on this snippet:

     if ! checkyesno "${SKIPNOCARRIER:-no}" && ip link show dev 
"$INTERFACE" | fgrep -q "NO-CARRIER"; then
         sleep ${CARRIER_TIMEOUT:-2} # Some cards are plain slow to come 
up. Don't fail immediately.
         if ip link show dev "$INTERFACE" | fgrep -q "NO-CARRIER"; then
             report_iproute "No connection"
         fi
     fi


And if I bring up the connection with the old rc.conf syntax, 'ip link 
show dev eth0' indeed shows:

2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast 
state DOWN qlen 1000
     link/ether 00:30:67:8f:7c:a8 brd ff:ff:ff:ff:ff:ff

Which maybe means something to someone. ;)

At this point, I'm ready to chalk it up to the hardware. I can reboot my 
laptop, and the light on the router that indicates that it sees the 
ethernet cable will only turn off for a second here and there throughout 
the shutdown/boot process. I do the same with this machine, and don't 
see so much as a flicker. I tried downloading and booting from an ubuntu 
live cd and didn't have any luck getting a connection. And both of my 
machines are using the same NIC (at least according to lspci), and 
should be at roughly the same version of the applicable software -- I 
updated my laptop an hour, at most, before I updated my desktop.