Debian Network Configuration

First, get network adapter name from ifconfig (nice if it is eth0)

Note, replace eth0 with whatever is in ifconfig

edit /etc/network/interfaces

and add 

auto eth0

allow-hotplug eth0
iface eth0 init dhcp 

OR

auto eth0
allow-hotplug eth0
iface eth0 inet dhcp 
address 192.168.254.10
netmask 255.255.255.0
gateway 192.168.254.254
dns-domain somewhere.com
dns-nameservers 8.8.8.8

shutdown the connection with;

ifdown -a

bring it back up with;

ifup -a

The -a flag affects all interfaces marked with auto.

check with;

ifconfig

Network manager will manage interfaces not listed in /etc/network/interfaces

ifup eth0 is the same as ifconfig  eth0 up and similarly, ifdown eth0 is the same as ifconfig eth0 down

 

To start/stop network manager, do

/etc/init.d/network-manager start/stop/restart

and similarly with wicd

/etc/init.d/wicd start/stop/restart

A note on Slackware, the configuration file of interest is;

/etc/rc.d/rc.inet1.conf

and while we can use ifconfig  eth0 up or ifconfig eth0 down to start or stop the interfaces, we should just use /etc/rc.d/rc.inet1

For example /etc/rc.d/rc.inet1 up (or start) to start or bring all configured interfaces up, down (or stop) does the opposite.

We can also use /etc/rc.d/rc.inet1 eth0_start or
/etc/rc.d/rc.inet1 eth0_stop to start/stop individual interfaces.