network-manager no longer starts automatically

Solution 1:

Your problem is that you have removed the file /etc/network/interfaces; you need this file.

The network configuration hangup at boot time is a common issue. To recreate the file, open a terminal and execute the following command:

sudo nano /etc/network/interfaces

Then, copy and paste the following into the file:

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
#
# The loopback network interface
auto lo
iface lo inet loopback

Press CTRL + o and then press ENTER to save the file. Press CTRL + x to exit the file.

Restart network-manager:

sudo service network-manager restart

Finally, to make it start up automatically execute the following command:

sudo update-rc.d network-manager defaults

Reboot to check your work.

Please post any errors or fail.

If that doesn't work, edit /etc/init/failsafe.conf:

sudo nano /etc/init/failsafe.conf

Look for "sleep" and change the number from 20 to 5 so that it looks like this:

sleep 5

Then comment out the following lines by placing a # at the beginning of each line so they look like this:

# $PLYMOUTH message --text="Waiting for network configuration..." || :
# sleep 40

# $PLYMOUTH message --text="Waiting up to 60 more seconds for network configuration..." || :
# sleep 59

This changes the wait time from 2 minutes to 5 seconds.

One last thing you can do is reinstall network-manager to replace any missing files:

sudo apt-get install --reinstall network-manager