How To Configure a Static IP on RHEL 8

Configuring a static IP address on RHEL 8 (Red Hat Enterprise Linux 8) is a fundamental networking task that ensures your server or system has a fixed IP address, which is crucial for seamless communication within a network. Unlike dynamic IP addresses assigned by DHCP, a static IP remains constant, making it ideal for servers, printers, or other devices that require consistent access. This guide will walk you through the steps to configure a static IP address on RHEL 8 using both the terminal and NetworkManager tools, ensuring your system is set up for reliable and efficient network performance.

Using nmcli To configure a Static IP Address​

Step 1: Show Available Network Interfaces​

Run the following command to display all available network interfaces:

[root@atiq ~]# nmcli connection show
NAME UUID TYPE DEVICE
ens160 e7d8560a-4538-406f-b3d2-c03a4996f6c1 ethernet ens160

In this example, the interface is ens160

Step 2: Modify the Network Interface Configuration​

Use the following command to set the static IP address, gateway, and DNS for the network interface:

[root@atiq ~]# nmcli connection modify ens160 \
ipv4.addresses 192.168.191.39/24 \
ipv4.gateway 192.168.191.1 \
ipv4.dns 8.8.8.8 \
ipv4.method manual \
connection.autoconnect yes

Step 3: Bring Up the Interface​

Activate the network interface to apply the new settings:

[root@atiq ~]# nmcli connection up ens160

nmcli is a command-line interface for NetworkManager, which can be used to obtain information or configure network interfaces.

Detailed Steps to Configure a Static IP Address​

Step 1: Set IPv4 Address​

To set the IPv4 address for a specific interface (e.g., enp0s3), use the following command:

# nmcli con mod enp0s3 ipv4.addresses 192.168.20.170/24

Step 2: Set the Gateway IP​

Specify the gateway IP address:

# nmcli con mod enp0s3 ipv4.gateway 192.168.20.1

Step 3: Enable Manual IP Configuration​

Inform the interface to use manual IP configuration instead of DHCP:

# nmcli con mod enp0s3 ipv4.method manual

Step 4: Set the DNS Server​

Add a DNS server IP address:

# nmcli con mod enp0s3 ipv4.dns "8.8.8.8"

Step 5: Reload the Interface Configuration​

# nmcli con up enp0s3

Apply the changes by reloading the network interface configuration:

Configuration File Overview

The changes made will be saved in the corresponding network configuration file under /etc/sysconfig/network-scripts/. You can verify the configuration using the following command:

# cat /etc/sysconfig/network-scripts/ifcfg-enp0s3

Sample Configuration File (ifcfg-enp0s3)

Below is an example of a generated configuration file:

TYPE="Ethernet"
BOOTPROTO="none"
NAME="enp0s3"
IPADDR="192.168.20.170"
NETMASK="255.255.255.0"
GATEWAY="192.168.20.1"
DEVICE="enp0s3"
ONBOOT="yes"
PROXY_METHOD="none"
BROWSER_ONLY="no"
PREFIX="24"
DEFROUTE="yes"
IPV4_FAILURE_FATAL="no"
IPV6INIT="no"
UUID="3c36b8c2-334b-57c7-91b6-4401f3489c69"

By following these steps, you can successfully configure a static IP address on RHEL 8, ensuring stable and reliable network connectivity for your system.