Ubuntu – No internet after upgrading from 12.04 to 14.04.1


I have a Dell Latitude with Ethernet and Wireless (broadcomm) adapters. They were both working fine on 12.04.
I upgraded to 14.04.1 via the Software Manager. Since then I am unable to connect to the internet. Some info:

  • I can connect to my wireless router
  • I do get DHCP info from my router for both wireless and Ethernet
  • When I boot to a sysrescuecd (the current version), I get internet access on both Ethernet and wireless.
  • nm-tool shows me the same IP, prefix, gateway, and DNS in sysrescuecd as I get in Ubuntu.

Things I've tried:
– I've tried setting the managed=true in the NetworkManager.conf file
– tried setting the IPv6 to ignored (could not figure out how to disable it).
– ping www.google.com fails (I think the error is 'unknown host' but I forgot to write it down)

Any help or would be GREATLY appreciated; my searching thus far has not seemed to find a universal cure (the last 'cure' I saw was a clean install of 14.04.1)

Thanks in advance.

** UPDATE **
AzkerM and Wild Man,

First off, thanks so much for your quick response – each time I use this forum, I am impressed by folks like you who are so willing.

I was able to resolve the issue – see below – but if someone could please tell me why it resolved the issue, I think I'll gain a better understanding.

I was able to solve my issue by running

sudo dhclient

I found that in the following question at askubuntu

Can someone please let me know why this would solve the issue?

Best Answer

I was able to solve my issue by running

sudo dhclient
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