How to Set Static IP Address and Configure Network in Linux

If you are a Linux system administrator, time will come when you will need to configure networking on your system. Unlike desktop machines where you can use dynamic IP addresses, on a server infrastructure, you will need to setup a static IP address (at least in most cases).

Read Also: How to Set or Change System Hostname in Linux

IP address: 192.168.0.100
Netmask: 255.255.255.0
Hostname: node01.tecmint.com
Domain name: tecmint.com
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:

To configure static IP address in RHEL / CentOS / Fedora, you will need to edit:

/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=node01.tecmint.com
GATEWAY=192.168.0.1
NETWORKING_IPV6=no
IPV6INIT=no

Next open:

# 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="node01.tecmint.com"
HWADDR="00:19:99:A4:46:AB"
IPADDR="192.68.0.100"
NETMASK="255.255.255.0"
NM_CONTROLLED="yes"
ONBOOT="yes"
TYPE="Ethernet"
UUID="8105c095-799b-4f5a-a445-c6d7c3681f07"

You will only need to edit the settings for:

1. DNS1 and DNS2
2. GATEWAY
3. HOSTNAME
4. NETMASK
5. 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 192.168.0.100
  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.