eth0 has disappeared - Debian

[Unkoerl]

If you perform 'ifconfig' and find eth0 missing, here is what is most likely the problem:-

When you check the network interfaces it will most likely appear as below:

it-etch:/$ cat /etc/network/interfaces

# 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

# The primary network interface
allow-hotplug eth0
iface eth0 inet static
address 192.168.0.4
netmask 255.255.255.0
gateway 192.168.0.1

If this is the case, 'allow-hotplug eth0' can cause the issue.

You will need to change 'allow-hotplug eth0' to 'auto eth0' and this should resolve the issue.