Thread: Wired LAN eth0 not detecting link/not working

hi everyone,

unable make eth0 work , thought wise guys can guide me solution.

problem: wired lan eth0 not detecting link/not working
hardware: dell e1505 laptop
os: ubuntu 11.10 server 32 bit (3.0.0-12-generic-pae #20-ubuntu smp)
note: wireless working fine. ndiswrapper not installed. sta module not loaded

troubleshooting steps done:
1. changed cables , switch ports.
2. ifup/ifdown, laptop powercycle.
3. ethtool setting eth0 parameters auto neg on/off, different speeds/duplex

related information:
===============================
#ifconfig -a
eth0 link encap:ethernet hwaddr 00:15:c5:20xx
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:17

lo link encap:local loopback
inet addr:127.0.0.1 mask:255.0.0.0
inet6 addr: ::1/128 scope:host
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)

wlan0 link encap:ethernet hwaddr 00:13:02:a1:yx:yx
inet addr:192.168.100.51 bcast:192.168.100.255 mask:255.255.255.0
inet6 addr: fe80::213:2ff:fea1xx/64 scope:link
broadcast running multicast mtu:1500 metric:1
rx packets:3130 errors:0 dropped:0 overruns:0 frame:0
tx packets:1886 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
rx bytes:272444 (272.4 kb) tx bytes:346431 (346.4 kb)
===============================

#cat /etc/network/interfaces
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
auto wlan0
iface wlan0 inet dhcp
wpa-ssid dontconnect
wpa-ap-scan 1
wpa-key-mgmt wpa-psk
wpa-psk xxxxxxxxxxxxxxxxxxxxxxxxx
===============================

#lshw -c network
*-network
description: wireless interface
product: pro/wireless 3945abg [golan] network connection
vendor: intel corporation
physical id: 0
bus info: pci@0000:0b:00.0
logical name: wlan0
version: 02
serial: 00:13:02:a1:yx:yx
width: 32 bits
clock: 33mhz
capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
configuration: broadcast=yes driver=iwl3945 driverversion=3.0.0-12-generic-pae firmware=15.32.2.9 ip=192.168.100.51 latency=0 link=yes multicast=yes wireless=ieee 802.11abg
resources: irq:42 memory:dfdff000-dfdfffff
*-network
description: ethernet interface
product: bcm4401-b0 100base-tx
vendor: broadcom corporation
physical id: 0
bus info: pci@0000:03:00.0
logical name: eth0
version: 02
serial: 00:15:c5:20:yx:yx
size: 10mbit/s
capacity: 100mbit/s
width: 32 bits
clock: 33mhz
capabilities: pm bus_master cap_list ethernet physical mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=b44 driverversion=2.0 duplex=half latency=64 link=no multicast=yes port=twisted pair speed=10mbit/s
resources: irq:17 memory:df9fe000-df9fffff
===============================

#lspci -v|egrep -a 7 -i net
03:00.0 ethernet controller: broadcom corporation bcm4401-b0 100base-tx (rev 02)
subsystem: dell inspiron 6400
flags: bus master, fast devsel, latency 64, irq 17
memory @ df9fe000 (32-bit, non-prefetchable) [size=8k]
capabilities: <access denied>
kernel driver in use: b44
kernel modules: b44

--
0b:00.0 network controller: intel corporation pro/wireless 3945abg [golan] network connection (rev 02)
subsystem: intel corporation device 1020
flags: bus master, fast devsel, latency 0, irq 42
memory @ dfdff000 (32-bit, non-prefetchable) [size=4k]
capabilities: <access denied>
kernel driver in use: iwl3945
kernel modules: iwl3945
===============================

#egrep -v "^$|^#" /etc/modprobe.d/blacklist.conf
blacklist evbug
blacklist usbmouse
blacklist usbkbd
blacklist eepro100
blacklist de4x5
blacklist eth1394
blacklist snd_intel8x0m
blacklist snd_aw2
blacklist i2c_i801
blacklist prism54
blacklist bcm43xx
blacklist garmin_gps
blacklist asus_acpi
blacklist snd_pcsp
blacklist pcspkr
blacklist amd76x_edac
===============================

#lsmod |egrep "ss|b4|iw"
iwl3945 73370 0
iwl_legacy 71499 1 iwl3945
mac80211 272785 2 iwl3945,iwl_legacy
cfg80211 172392 3 iwl3945,iwl_legacy,mac80211
b44 31395 0
ssb 50682 1 b44
===============================

#modinfo b44
filename: /lib/modules/3.0.0-12-generic-pae/kernel/drivers/net/b44.ko
version: 2.0
license: gpl
description: broadcom 44xx/47xx 10/100 pci ethernet driver
author: felix fietkau, florian schirmer, pekka pietikainen, david s. miller
srcversion: 8729399e9471704d13404c1
alias: ssb:v4243id0806rev*
alias: pci:v000014e4d0000170csv*sd*bc*sc*i*
alias: pci:v000014e4d00004402sv*sd*bc*sc*i*
alias: pci:v000014e4d00004401sv*sd*bc*sc*i*
depends: ssb
vermagic: 3.0.0-12-generic-pae smp mod_unload modversions 686
parm: b44_debug:b44 bitmapped debugging message enable value (int)
===============================

#modinfo ssb
filename: /lib/modules/3.0.0-12-generic-pae/kernel/drivers/ssb/ssb.ko
license: gpl
description: sonics silicon backplane driver
srcversion: 7e7e756f6d56de7c6587290
alias: pci:v000014e4d0000432bsv*sd*bc*sc*i*
alias: pci:v000014e4d00004329sv*sd*bc*sc*i*
alias: pci:v000014e4d00004328sv*sd*bc*sc*i*
alias: pci:v000014e4d00004325sv*sd*bc*sc*i*
alias: pci:v000014e4d00004324sv*sd*bc*sc*i*
alias: pci:v000014e4d00004321sv*sd*bc*sc*i*
alias: pci:v000014e4d00004320sv*sd*bc*sc*i*
alias: pci:v000014e4d00004319sv*sd*bc*sc*i*
alias: pci:v000014a4d00004318sv*sd*bc*sc*i*
alias: pci:v000014e4d00004318sv*sd*bc*sc*i*
alias: pci:v000014e4d00004315sv*sd*bc*sc*i*
alias: pci:v000014e4d00004312sv*sd*bc*sc*i*
alias: pci:v000014e4d00004311sv*sd*bc*sc*i*
alias: pci:v000014e4d00004307sv*sd*bc*sc*i*
alias: pci:v000014e4d00004306sv*sd*bc*sc*i*
alias: pci:v000014e4d00004301sv*sd*bc*sc*i*
depends:
vermagic: 3.0.0-12-generic-pae smp mod_unload modversions 686
===============================

#grep -i eth /var/log/syslog
jan 12 12:58:51 whale kernel: [ 1.236149] ssb: core 0 found: fast ethernet (cc 0x806, rev 0x07, vendor 0x4243)
jan 12 12:58:51 whale kernel: [ 1.300660] b44 ssb0:0: eth0: broadcom 44xx/47xx 10/100baset ethernet 00:15:c5:20:90:57
jan 12 12:58:51 whale kernel: [ 14.656875] addrconf(netdev_up): eth0: link not ready
jan 12 12:58:51 whale dhclient: dhcpdiscover on eth0 255.255.255.255 port 67 interval 3
jan 12 12:58:54 whale dhclient: dhcpdiscover on eth0 255.255.255.255 port 67 interval 7

===============================
#dmesg|egrep -i "eth|iw|b44|ssb"
[ 1.200551] b44 0000:03:00.0: pci int -> gsi 17 (level, low) -> irq 17
[ 1.236149] ssb: core 0 found: fast ethernet (cc 0x806, rev 0x07, vendor 0x4243)
[ 1.236160] ssb: core 1 found: v90 (cc 0x807, rev 0x03, vendor 0x4243)
[ 1.236168] ssb: core 2 found: pci (cc 0x804, rev 0x0a, vendor 0x4243)
[ 1.277185] ssb: sonics silicon backplane found on pci device 0000:03:00.0
[ 1.277233] b44: b44.c:v2.0
[ 1.300660] b44 ssb0:0: eth0: broadcom 44xx/47xx 10/100baset ethernet 00:15:c5:20:90:57
[ 10.258394] iwl3945: intel(r) pro/wireless 3945abg/bg network connection driver linux, in-tree:s
[ 10.258400] iwl3945: copyright(c) 2003-2011 intel corporation
[ 10.258490] iwl3945 0000:0b:00.0: pci int -> gsi 16 (level, low) -> irq 16
[ 10.258507] iwl3945 0000:0b:00.0: setting latency timer 64
[ 10.314272] iwl3945 0000:0b:00.0: tunable channels: 11 802.11bg, 13 802.11a channels
[ 10.314278] iwl3945 0000:0b:00.0: detected intel wireless wifi link 3945abg
[ 10.314435] iwl3945 0000:0b:00.0: irq 42 msi/msi-x
[ 10.831615] ieee80211 phy0: selected rate control algorithm 'iwl-3945-rs'
[ 14.656875] addrconf(netdev_up): eth0: link not ready
[ 14.999914] iwl3945 0000:0b:00.0: loaded firmware version 15.32.2.9
===============================

#ethtool eth0
settings eth0:
supported ports: [ mii ]
supported link modes: 10baset/half 10baset/full
100baset/half 100baset/full
supports auto-negotiation: yes
advertised link modes: 100baset/full
advertised pause frame use: symmetric receive-only
advertised auto-negotiation: yes
speed: 10mb/s
duplex: half
port: twisted pair
phyad: 1
transceiver: internal
auto-negotiation: on
mdi-x: unknown
supports wake-on: g
wake-on: d
current message level: 0x000000ff (255)
drv probe link timer ifdown ifup rx_err tx_err
link detected: no
===============================

help.

link detected: no

information you've provided it's significant, regarding problem. hardware issue, since swapped cables , changed switch ports i'd odds high ethernet port of laptop dead.

Forum The Ubuntu Forum Community Ubuntu Official Flavours Support Networking & Wireless [ubuntu] Wired LAN eth0 not detecting link/not working

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