Ask Ubuntu is a question and answer site for Ubuntu users and developers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I encounter problems during starting up Ubuntu 12.04 laptop. There is no internet connection (wired network connection is established though) and there is no error message from network manager or other system part.

In the very beginning, email is working but after 2-3 min it is not working anymore.

Other pcs are working (email & internet) without problem. Router shows that internet connection is alive.

After resetting router (and network connection as well), problem disappears till next boot.

Which error or log file should I look in to try resolving the problem?

share|improve this question

Can you show us the output of 'ifconfig' as soon as you boot and after the connection is dropped? Also, can execute 'route', see the IP of your default gateway, and try to ping it? For example:

jmhal@pluto:~$ ifconfig
wlan0     Link encap:Ethernet  Endereço de HW 00:22:43:44:a2:d3  
      inet end.:  Bcast:  Masc:
      endereço inet6: fe80::222:43ff:fe44:a2d3/64 Escopo:Link
      pacotes RX:336542 erros:0 descartados:0 excesso:0 quadro:0
      Pacotes TX:169868 erros:0 descartados:0 excesso:0 portadora:0
      colisões:0 txqueuelen:1000 
jmhal@pluto:~$ route
Tabela de Roteamento IP do Kernel
Destino         Roteador        MáscaraGen.    Opções Métrica Ref   Uso Iface 
default         UG    0      0        0 wlan0
link-local      *          U     1000   0        0 wlan0     *        U     2      0        0 wlan0
jmhal@pluto:~$ ping
PING ( 56(84) bytes of data.
64 bytes from icmp_req=1 ttl=64 time=52.1 ms

This way you'll be sure if the connection to the router is up or not.

share|improve this answer
Is this an answer or a question?? – chili555 Feb 13 '14 at 13:29
Both. Either or... – jmhal Feb 13 '14 at 21:01
Thank you jmhal, I just wait to see it happening once more, it is not in every boot. However I would like as well to search in the right log file to find the cause – bob Feb 14 '14 at 7:13

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.