What is a static IP address?

A static IP address is a fixed Internet Protocol (IP) address assigned to a device, which does not change over time. It serves as a unique identifier within a network, enabling it connect & communicate effectively.

It is recommended to assign a static IP address to a device, which is always stationary & connected to the same network. Assigning static IP address on a frequently moving device will result in conflicts and blocks from either connecting to a router or accessing internet.

Example:

  1. You set up a static IP address on your laptop connected to your home Wi-Fi network (192.168.1.1 as the router’s gateway).
interface wlan0
static ip_address=192.168.1.100/24
static routers=192.168.1.1
static domain_name_servers=8.8.8.8 8.8.4.4

This static IP address is configured to your router in home, you have a unique IP address and other devices can easily be connect/communicate with your device using this IP address, since it’s never going to be changed.

  1. You visit a coffee shop and connect to their Wi-Fi, where the router’s gateway is 192.168.0.1.
  • The static configuration on your laptop (192.168.1.x) does not match the coffee shop’s network range (192.168.0.x), causing an IP conflict or failure to connect.
  • Why is this happening ?
    • Your laptop tries to use 192.168.1.100 and expects 192.168.1.1 as the gateway.
    • The coffee shop’s router operates on a different subnet (192.168.0.x) and cannot route traffic correctly.

What is a Dynamic IP Address?

A dynamic IP address is a temporary address allocated to the device you connect to a network. The temporary address is assigned to a device by DHCP server (Device Host Configuration Protocol) when it connects to a network. Unlike static IP addresses, which remain constant, dynamic IP’s can change over time or when the device reconnects to the network.

It is to use recommended dynamic IP address when a device is frequently moving a lot and connects to different networks. Since the IP allocation is done by the network’s router DHCP, the IP address will change according to the router default gateway.

Note: Dynamic IP address is enabled by default in all other operating systems, it’s only the static IP address allocation done manually.

How to Assign a Static IP Address:

I looked at many “HowTo” videos, but I always ends up facing errors and we’re going to be manually assigning them with minimal
automated steps.

  1. Gather Network Information:
hostname -I
ip r | grep default
route | grep '^default' | grep -o '[^ ]*$'

Output from my device:

iamyaash@pi-server:~ $ ip r | grep default
default via 192.168.31.1 dev wlan0 src 192.168.31.35 metric 3003 
iamyaash@pi-server:~ $ route | grep '^default' | grep -o '[^ ]*$'
wlan0

Copy the gateway address(192.168.31.1) & interface name (wlan0).

  1. Edit the DHCP Configuration File: Install dhcpcd unless there isn’t any file named /etc/dhcpcd.conf:
sudo dnf install dhcpcd

sudo nano /etc/dhcpcd.conf

Add the following lines into the configuration file:

interface wlan0
static ip_address=<STATIC_IP>/24
static routers=192.168.31.1
static domain_name_servers=8.8.8.8 8.8.4.4

Use any <STATIC_IP>/24 to your liking. (Such as 192.168.31.253) Save and exit.

  1. Reboot the device to reflect the changes all over the system:
sudo reboot

After the restart, ensure that the static IP is assigned in hostname & the changes are reflected to /etc/resolv.conf.

hostname -I

cat /etc/resolv.conf

Follow these steps only if the Static IP Address is not Reflected anywhere

  1. Stop & Disable the systemd-resolved.service:
sudo systemctl stop systemd-resolved.service
sudo systemctl disable systemd-resolved.service

This will stop & disable the systemd-resolved.service, which no longer manages DNS resolution, allowing you to fully control the /etc/resolv.conf file.

  1. Remove the Symlink for /etc/resolv.conf:
sudo rm /etc/resolv.conf

Typically, the /etc/resolv.conf is linked to systemd-resolved`.

  1. Create a new /etc/resolv.conf & Manually Add the DNS Addresses:
sudo nano /etc/resolv.conf

nameserver 208.67.222.222
nameserver 208.67.220.220
nameserver 8.8.8.8

Save and exit.

  1. Restart the dhcpcd service:
sudo systemctl restart dhcpcd

Delete the existing IP, in case the older IPs are retained:

sudo ip addr del 192.168.31.102 dev wlan0
  • 192.168.31.102 - The IP that needs to be removed.
  • dev wlan0 - The interface name of the IP address.

If nothing works out, let’s change the static IP using nmcli:

  1. List the available networks
sudo nmcli connection show

This will show the available networks connected to your device. Output:

NAME                UUID                                  TYPE      DEVICE  
Wired connection 1  82aadf2b-xxxx-xxxx-a3ec-xxxxxxxxxxxx  ethernet  enp2s0  
lo                  e6b49b80-xxxx-xxxx-b8d7-xxxxxxxxxxxx  loopback  lo      
docker0             bfcf407f-xxxx-xxxx-bbfe-xxxxxxxxxxxx  bridge    docker0
  1. Modify the Wired connection 1 network:
sudo nmcli connection modify "Wired connection 1" ipv4.addresses 192.168.31.xx/24 ipv4.gateway 192.168.31.1  ipv4.dns "8.8.8.8 8.8.4.4" ipv4.method manual
  1. Restart the Connection After modifying the connection, restart it to apply the changes:
sudo nmcli connection down "Wired connection 1"
sudo nmcli connection up "Wired connection 1"`
  1. Verify the New IP Address Check if the static IP has been assigned successfully:
ip addr show wlan0 | grep inet
  1. If you don’t need IPv6, you can disable it for this connection (Optional):
sudo nmcli connection modify preconfigured ipv6.method ignore