How to Set Static IP Address and Configure Network in Linux

Being Linux system administrator, situations arises when it becomes necessary to configure networking on the system. Unlike desktop machines, where you can use dynamic IP addresses on a server infrastructure, you will need to setup a static IP address. Here is a guide to that.

IP address: 192.168.0.103 Netmask: 255.255.255.0 Hostname: hub01.tecniqa.com Domain name: tecniqa.blogspot.in Gateway: 192.168.0.1 DNS Server 1: 8.8.8.8 DNS Server 2: 4.4.4.4

Configure Static IP Address in RHEL/CentOS/Fedora

/etc/sysconfig/network
/etc/sysconfig/network-scripts/ifcfg-eth0

Where in the above "ifcfg-eth0" answers to your network interface eth0. If your interface is named “eth1" then the file that you will need to edit is "ifcfg-eth1".
Let’s start with the first file:

# vi /etc/sysconfig/network

Open that file and set:

NETWORKING=yes
HOSTNAME=hub01.tecniqa.com //change to your hostname
GATEWAY=192.168.0.1
NETWORKING_IPV6=no
IPV6INIT=no

Next open the following:

# vi /etc/sysconfig/network-scripts/ifcfg-eth0

Note: Make sure to open the file corresponding to your network interface. You can find your network interface name with ifconfig -a command.

In that file make the following changes:

DEVICE="eth0"
BOOTPROTO="static"
DNS1="8.8.8.8"
DNS2="4.4.4.4"
GATEWAY="192.168.0.1"
HOSTNAME="hub01.tecniqa.com"
HWADDR="01:23:95:E3:7F:AB"
IPADDR="192.68.0.103"
NETMASK="255.255.255.0"
NM_CONTROLLED="yes"
ONBOOT="yes"
TYPE="Ethernet"
UUID="8105c095-199b-4f5a-a445-b657c368170d"

You will only need to edit the settings for:

DNS1 & DNS2
GATEWAY
HOSTNAME
NETMASK
IPADDR

Other settings should have already been predefined.
Next edit resolve.conf file by opening it with a text editor such as nano or vi:

# vi /etc/resolv.conf

nameserver 8.8.8.8 # Replace with your nameserver ip
nameserver 4.4.4.4 # Replace with your nameserver ip

Once you have made your changes restart the networking with:

# /etc/init.d/network restart  [On SysVinit]
# systemctl restart network    [On SystemD]

Set Static IP Address in Debian / Ubuntu

To setup static IP address in Debian/ Ubuntu, open the following file:

# nano /etc/network/interfaces

You may see a line looking like this:

auto eth0
iface eth0 inet dhcp

Change it so it looks like this:

auto eth0
iface eth0 inet static 
  address 192.168.0.103
  netmask 255.255.255.0
  gateway 192.168.0.1
  dns-nameservers 4.4.4.4
  dns-nameservers 8.8.8.8

Save the file and then edit /etc/resolv.conf like this:

# nano /etc/resolv.conf

nameserver 8.8.8.8 # Replace with your nameserver ip
nameserver 4.4.4.4 # Replace with your nameserver ip

Restart the networking on your system with:

# /etc/init.d/network restart  [On SysVinit]
# systemctl restart network    [On SystemD]

Your static IP address has been configured.

Conclusion:

You now know how to configure a static IP address on a Linux distro. If you have any questions or comments, please do not hesitate to submit them in the comment section below.