12.04 Ethernet works sporadically

[ravikanth1988]

machine: lenovo x200 tablet
This is what I got from ifconfig when ethernet is not working

eth0      Link encap:Ethernet  HWaddr 00:1f:16:1a:0e:7e         
inet6 addr: fe80::21f:16ff:fe1a:e7e/64 Scope:Link
UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
RX packets:34 errors:0 dropped:0 overruns:0 frame:0
TX packets:387 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000 
RX bytes:16036 (16.0 KB)  TX bytes:98315 (98.3 KB)
Interrupt:20 Memory:f2700000-f2720000  


lo        Link encap:Local Loopback  
inet addr:127.0.0.1  Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING  MTU:16436  Metric:1
RX packets:704 errors:0 dropped:0 overruns:0 frame:0
TX packets:704 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0 
RX bytes:55280 (55.2 KB)  TX bytes:55280 (55.2 KB)

The following is the ifconfig when ethernet is working

 eth0      Link encap:Ethernet  HWaddr 00:1f:16:1a:0e:7e
inet addr:10.5.48.125  Bcast:10.5.51.255  Mask:255.255.252.0
inet6 addr: fe80::21f:16ff:fe1a:e7e/64 Scope:Link
UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
RX packets:32899 errors:0 dropped:0 overruns:0 frame:0
TX packets:22710 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000 
RX bytes:41546832 (41.5 MB)  TX bytes:2607896 (2.6 MB)
Interrupt:20 Memory:f2700000-f2720000  

lo        Link encap:Local Loopback  
inet addr:127.0.0.1  Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING  MTU:16436  Metric:1
RX packets:2014 errors:0 dropped:0 overruns:0 frame:0
TX packets:2014 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0 
RX bytes:173578 (173.5 KB)  TX bytes:173578 (173.5 KB)

At the moment I am posting from Ubuntu 12.04.

[NikTh]

What is 12.01 ? Did you mean 12.10 ? Cause 12.10 is in development state.. (Alpha) .

If you mean 12.04 , then check your internet connection. Check 1) Router , 2) Cables , 3) Filters or splitters , 4) your provider (call them) .

[Gone fishing]

In network connections try disabling IPv6

i.e. select edit connections > select the IPv6 tab > in method select ignore > save

[ravikanth1988]

Damn it is 12.04.

[ravikanth1988]

Just tried ignoring the IPV6 as suggested. Still it does not work. I tried ifconfig after disabling. I did not notice any change. can you look into that?

eth0      Link encap:Ethernet  HWaddr 00:1f:16:1a:0e:7e   
           inet6 addr: fe80::21f:16ff:fe1a:e7e/64 Scope:Link
           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
           RX packets:4 errors:0 dropped:0 overruns:0 frame:0
           TX packets:51 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:1000  
           RX bytes:2376 (2.3 KB)  TX bytes:12423 (12.4 KB)
           Interrupt:20 Memory:f2700000-f2720000  
 

 lo        Link encap:Local Loopback   
           inet addr:127.0.0.1  Mask:255.0.0.0
           inet6 addr: ::1/128 Scope:Host
           UP LOOPBACK RUNNING  MTU:16436  Metric:1
           RX packets:16 errors:0 dropped:0 overruns:0 frame:0
           TX packets:16 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:0  
           RX bytes:1312 (1.3 KB)  TX bytes:1312 (1.3 KB)

[ravikanth1988]

By the way. I have this 12.04 on dual boot with windows 7. The ethernet works perfectly fine in windows 7. It only has problems with Ubuntu 12.04. I am assuming this means that there is no problem with the router,cables, ISP.

[ravikanth1988]

I tried some diagnostics suggested by chilli in another thread. I dont know if they can help in the diagnosis.

ravikanth@ravikanth-ThinkPad-X200-Tablet:~$ dmesg | grep eth0
 

 [    2.178533] e1000e 0000:00:19.0: eth0: (PCI Express:2.5GT/s:Width x1) 00:1f:16:1a:0e:7e
 [    2.178537] e1000e 0000:00:19.0: eth0: Intel(R) PRO/1000 Network Connection
 [    2.178565] e1000e 0000:00:19.0: eth0: MAC: 7, PHY: 8, PBA No: 1008FF-0FF
 [   17.106451] ADDRCONF(NETDEV_UP): eth0: link is not ready
 [   18.032366] ADDRCONF(NETDEV_UP): eth0: link is not ready
 [   18.032736] ADDRCONF(NETDEV_UP): eth0: link is not ready
 [   19.657359] e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
 [   19.657365] e1000e 0000:00:19.0: eth0: 10/100 speed: disabling TSO
 [   19.657572] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
 [   30.128089] eth0: no IPv6 routers present
 [   78.840058] eth0: no IPv6 routers present
 [  126.872097] eth0: no IPv6 routers present
 [  174.040065] eth0: no IPv6 routers present
 [  233.136075] eth0: no IPv6 routers present

ravikanth@ravikanth-ThinkPad-X200-Tablet:~$ nm-tool
 

 NetworkManager Tool
 

 State: disconnected
 

 - Device: wlan0 ----------------------------------------------------------------
   Type:              802.11 WiFi
   Driver:            iwlwifi
   State:             unavailable
   Default:           no
   HW Address:        00:22:FA:95:D1:C6
 

   Capabilities:
 

   Wireless Properties
     WEP Encryption:  yes
     WPA Encryption:  yes
     WPA2 Encryption: yes
 

   Wireless Access Points  
 

 

 - Device: eth0 -----------------------------------------------------------------
   Type:              Wired
   Driver:            e1000e
   State:             disconnected
   Default:           no
   HW Address:        00:1F:16:1A:0E:7E
 

   Capabilities:
     Carrier Detect:  yes
     Speed:           100 Mb/s
 

   Wired Properties
     Carrier:         on

[Gone fishing]

As you still have a IPv6 address and no IPv4 address it seems the IPv6 isn't disabled have a look at http://www.ubuntuvibes.com/2011/01/q...in-ubuntu.html

[ravikanth1988]

I tired both methods to shut down IPV6. I dont think it is working. Look a the follwong

ravikanth@ravikanth-ThinkPad-X200-Tablet:~$ ip a | grep inet
    inet 127.0.0.1/8 scope host lo

[Gone fishing]

What happens if you manually set the IPv4 address and then try and ping the router?