DHCP and network configuration

Hostname and network configuration

Get the current status

Get connection details

Display connection settings

ifconfig

if you have many network card you can filter using interface name (eth0 // eth1 // wlan0).

To get more details

ifconfig -a

Discover your gateway

route

Default gateway is named "default"

Setup DHCP / static IP @

By default the system is using DHCP.

Following procedure will set a fix IP.

Edit configuration file:

vim /etc/network/interfaces

Adjust the file like this:

# The loopback network interface (127.0.0.1)
auto lo
iface lo inet loopback

# The primary network interface [DHCP]
#allow-hotplug eth0
#auto eth0
#iface eth0 inet dhcp


# The primary network interface [static IP]
auto eth0
iface eth0 inet static
        address 192.168.0.100				# mandatory
        netmask 255.255.255.0				# mandatory
        gateway 192.168.0.1				# mandatory
        network 192.168.0.0				
        broadcast 192.168.0.255
        dns-nameservers 8.8.8.8 8.8.4.4                 # Google DNS

Then, restart configuration

/etc/init.d/networking restart

Wifi

WEP

Edit:

vim /etc/network/interfaces

Add:

Wifi configuration [WEP]
auto wlan0
iface wlan0 inet dhcp
  wireless-essid NUMERICABLE-F164
  wireless-key f4c1dc12023b916d309c2561cb
  wireless-channel 11
  wireless-mode managed

WPA

Required software

You must install wpa supplicant

apt-get install wpasupplicant

Restrict the permissions of interfaces configuration to prevent code disclosure:

chmod 0600 /etc/network/interfaces

Configuration

Edit

vim /etc/network/interfaces

Adjust like that:

auto wlan0
iface wlan0 inet dhcp 
    wpa-ssid ssid
    wpa-psk password

Take changes into account

Then, you have to start your wireless interface:

ifup wlan0

Restart configuration

/etc/init.d/networking restart

Setup hostname Hosts

Edit configuration file

1. vi /etc/hosts

127.0.0.1 localhost.localdomain localhost 192.168.0.100 server1.example.com server1

1. The following lines are desirable for IPv6 capable hosts

1 ip6-localhost ip6-loopback

fe00::0 ip6-localnet ff00::0 ip6-mcastprefix ff02::1 ip6-allnodes ff02::2 ip6-allrouters ff02::3 ip6-allhosts

Hostname

1. echo server1.example.com > /etc/hostname

Take changes into account Reboot server

1. shutdown -r now

Check result

1. hostname
2. hostname -f

You should have 2 similar results: server1.example.com