Internet connection suddenly missing in Ubuntu 14.04

Question

I have a dual-boot ThinkPad Edge E330 laptop (Ubuntu 14.04 /win10). I have had so far no problems with Ubuntu. This morning I started my session and I noticed that the laptop was not even trying to connect to the wifi network. No trace of connection is found after plugging the ethernet wire, either. In my previous session I just had a console apt-get upgrade. In windows, everything is just fine, so I suspect a damaged driver for the PCIe card. My current kernel is 3.13.0-46-generic The following info should be relevant:

sudo lshw -c network

*-network               
   description: Network controller
   product: BCM43228 802.11a/b/g/n
   manufacturer: Broadcom Corporation
   physical id: 0
   bus info: pci@0000:02:00.0
   version: 00
   width: 64 bits
   clock: 33MHz
   capabilities: pm msi pciexpress bus_master cap_list
   config: driver=bcma-pci-bridge latency=0
   resources: irq:17 memoria:f1500000-f1503fff

 *-network DEACTIVATED
      descripction: Ethernet interface
      product: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller
      manufacturer: Realtek Semiconductor Co., Ltd.
      phys. id: 0
      bus info: pci@0000:08:00.0
      logical name: eth0
      version: 07
      serie: 3c:97:0e:e5:7d:ec
      size: 1Gbit/s
      capacity: 1Gbit/s
      width: 64 bits
      clock: 33MHz
      capabilities: pm msi pciexpress msix vpd bus_master cap_list   ethernet     physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
   config: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full latency=0 link=no multicast=yes port=MII speed=1Gbit/s
   resources: irq:43 ioport:2000(size=256) memory:f0c04000-f0c04fff memory:f0c00000-f0c03fff

ifconfig -a

     eth0      Link encap:Ethernet  adressHW 3c:97:0e:e5:7d:ec  
               DIFUSION MULTICAST  MTU:1500  Métrica:1
               Packets RX:0 errors:0 lost:0 overruns:0 frame:0
               Packets TX:0 errors:0 lost:0 overruns:0 carrier:0
               colisions:0 long.colaTX:1000 
               Bytes RX:0 (0.0 B)  TX bytes:0 (0.0 B)

   lo        Link encap: local loop  
             Address inet:127.0.0.1  Mask:255.0.0.0
             Address inet6: ::1/128 Range:Host
             ACTIVE WORKING LOOP  MTU:65536  Metric:1
             Packets RX:1153 errors:0 lost:0 overruns:0 frame:0
             Packets TX:1153 errors:0 lost:0 overruns:0 carrier:0
             colisions:0 long.colaTX:0 
             Bytes RX:103441 (103.4 KB)  TX bytes:103441 (103.4 KB)

lspci -vvnn | grep -i net

02:00.0 Network controller [0280]: Broadcom Corporation BCM43228 802.11a/b/g/n [14e4:4359]
   Subsystem: Broadcom Corporation Device [14e4:0607]
08:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd.      RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev07)

sudo rfkill list all

  1: tpacpi_bluetooth_sw: Bluetooth
      Soft blocked: yes
      Hard blocked: no

It looks very similar to 14.04 - Network manager stopped working, but here the system does not display any internal error, and the drivers may add some extra dificulties.

Please, keep in mind that I can only try offline solutions. And thank you so much for your help!!

Answer 1

I had the same thing happen to me this morning. I had to go to another network working linux machine and execute these commands to save the pre-upgrade packages to a usb stick:

$ wget http://mirrors.kernel.org/ubuntu/pool/main/libn/libnl3/libnl-3-200_3.2.21-1_amd64.deb
$ wget http://mirrors.kernel.org/ubuntu/pool/main/libn/libnl3/libnl-route-3-200_3.2.21-1_amd64.deb
$ wget http://mirrors.kernel.org/ubuntu/pool/main/libn/libnl3/libnl-genl-3-200_3.2.21-1_amd64.deb

Then, insert the usbstick in the problem machine, mount it, cd the directory where your files are and execute the command:

$ sudo dpkg -i libnl-*.deb

...and the reboot. That should fix your network issue.

Ubuntu will then want you to upgrade those packages again. I did that and it broke mine again but someone else reported that more packages came up to upgrade and upgrading all of them fixed the original issue.

Answer 2

P. Miller's answer put me in the right track. It is solved now. What I finally did is:

1. To downgrade the libn libraries as suggested. Although it is not necessary, I also downgraded the kernel to the previous version. This had my ethernet port blink again, but I had no connectivity yet.

2. For the ethernet I wrote

   sudo ifconfig eth0 up
   sudo dhclient eth0
   

   This is not permanent, but you can edit /etc/rc.local (sudo gedit /etc/rc.local) and insert sudo dhclient eth0, so that the final result is:

    #!/bin/sh -e
    #
    # rc.local
    #
    # This script is executed at the end of each multiuser runlevel.
    # Make sure that the script will "exit 0" on success or any other
    # value on error.
    #
    # In order to enable or disable this script just change the execution
    # bits.
    #
    # By default this script does nothing.
    sudo dhclient eth0
    exit 0
   

   After rebooting, ethernet was working again.

3. Recovering the wifi took longer. In my case, being a Broadcom card, the usual b43 driver did not work, while the suggested one in Software and updates -> Additional drivers, did (bcmwl-kernel-source). Just click to accept the suggestion. In principle, it will produce the file /etc/modprobe.d/blacklist-bcm43.conf blacklisting the rival modules. To make sure that there are no interferences from b43, you can type

   sudo modprobe -rv b43
   

   Dependencies are updated with

   sudo depmod -a
   

   Finally, to access the missing wifi icon in the taskbar (nm-applet), I did as in other threads:

   sudo apt-get install indicator-applet indicator-network
   sudo apt-get install --reinstall network-manager-gnome
   

Once again, after a final reboot, wifi was back again. I hope this can help you.