networking disabled on laptop running ubuntu 16.10

[Ralf Mardorf]

On Fri, 11 Nov 2016 07:02:42 +0100, M. Fioretti wrote:
>ABOUT THE WINDOWS BUTTON: it is on.

I have the impression that Windows software could disable the button
and perhaps no matter what the Wifi button shows, Wifi could be
disabled. It might be that you need to enable Wifi with Windows
software.

Apart from this, is LAN enabled by the BIOS settings?

>I am ready to type the whole Ethernet configuration by hand, at this 
>point that is edit the several interfaces/ifup/ifdown scripts and
>config files

This still requires that the interfaces are available.

What's the output of

  ls /sys/class/net/

or

  ifconfig

?

If a device is available, you could write a script and start it by a
unit.

My script simply runs

  dhcpcd $(basename $(ls -d /sys/class/net/enp?s0))

resp. for PPPoE

  modprobe -v pppoe
  ip link set $(basename $(ls -d /sys/class/net/enp?s0)) up
  pon

perhaps instead of

  $(basename $(ls -d /sys/class/net/enp?s0))

try

  $(ifconfig | cut -d" " -f1 | head -1 | sed "s/:/ /")

or similar (depending on the shown interfaces), or try the name, but
note, the names are inconsistent, at least on tower PCs, if you even
add or remove a sound card.

A unit file

  /lib/systemd/system/your_script.service

could look like this

  [Unit]
  Description=Your DHCP or PPPoE

  [Service]
  Type=oneshot
  ExecStart=/usr/local/sbin/your_script.service start
  ExecStop=/usr/local/sbin/your_script.service stop
  RemainAfterExit=true

  [Install]
  WantedBy=multi-user.target

Regards,
Ralf