Introduction to Static IP Configuration
Assigning a static IP address to a network interface is an essential task for any network administrator or user who needs a constant IP address for their system. On Ubuntu, this can be achieved using various methods, ranging from editing network configuration files to using network management tools. In this tutorial, we’ll explore different ways to assign a static IP address on an Ubuntu system.
Prerequisites
Before getting started, make sure you have the following:
- An Ubuntu system
- Root privileges or the ability to use ‘sudo’
- A working knowledge of networking concepts
- An understanding of your network’s IP address structure
Method 1: Using Netplan
Since Ubuntu 17.10, Netplan has been introduced as the new method to configure network interfaces. Let’s start with the most basic way to assign a static IP using Netplan.
$ sudo nano /etc/netplan/*.yaml
Edit the Netplan YAML configuration file according to your needs. Below is a simple example:
network:
version: 2
renderer: networkd
ethernets:
enp0s3:
dhcp4: no
addresses:
- 192.168.1.100/24
gateway4: 192.168.1.1
nameservers:
addresses: [8.8.8.8, 8.8.4.4]
After editing, apply the changes:
$ sudo netplan apply
Check the new IP address:
$ ip addr show enp0s3
Method 2: Using /etc/network/interfaces
For older Ubuntu systems, or if you’ve uninstalled Netplan, you can configure your IP by editing the /etc/network/interfaces file.
$ sudo nano /etc/network/interfaces
Here is a basic static IP configuration:
auto enp0s3
iface enp0s3 inet static
address 192.168.1.100
netmask 255.255.255.0
gateway 192.168.1.1
dns-nameservers 8.8.8.8 8.8.4.4
Restart the networking service to apply changes:
$ sudo /etc/init.d/networking restart
Advanced Configuration
For a more advanced configuration, you can set multiple static IPs or configure VLANs. For instance, configuring a secondary IP address:
auto enp0s3
iface enp0s3 inet static
address 192.168.1.100
netmask 255.255.255.0
gateway 192.168.1.1
iface enp0s3:1 inet static
address 192.168.1.101
netmask 255.255.255.0
To configure a VLAN:
auto enp0s3.10
iface enp0s3.10 inet static
address 192.168.2.100
netmask 255.255.255.0
vlan-raw-device enp0s3
Troubleshooting
If your network is not functioning as expected after assigning a static IP, ensure your configuration files are correct, your cables are plugged in, and your network services are restarted. Checking the log files can provide useful information:
$ journalctl -u networkd
Conclusion
Assigning a static IP on Ubuntu can be straightforward once you’re familiar with Netplan or the traditional /etc/network/interfaces method. Utilize the one that is most suitable for your version of Ubuntu and specific networking requirements.
