Ubuntu Server: The Easy Way to Assign a Static IP

The Goal

To configure a static IP address on an Ubuntu server so that it remains reliably reachable by other systems—whether it's serving files, running applications, or hosting a database.

The Lab

In this setup:

• The server is called server1
• It has two NICs:
  • eth0 (already using DHCP)
  • eth1 (to be configured with a static IP)
• The desired IP configuration:
  • IP Address: 10.0.10.10/24
  • Gateway: 10.0.10.1
  • Name Servers: 10.0.10.1
• Configuration is managed using Ubuntu's netplan utility

The Why

Servers that provide persistent services—whether for internal users or other servers—must be reliably addressable. DHCP assigns addresses dynamically, which risks change. Static IPs eliminate that uncertainty and ensure service availability across reboots or network reassignments.

The How

1. Identify the NICs

Run:

ip a

This lists all interfaces and shows which ones are active and which have IPs. In this case, eth0 uses DHCP; eth1 is unconfigured.

2. Review Netplan Files

Netplan stores network settings in YAML format under:

/etc/netplan/

Run:

ls /etc/netplan

View current config:

sudo cat /etc/netplan/<filename>.yaml

The file will show DHCP set to true for eth0.

3. Set a Static IP Using Netplan’s CLI

Use netplan set to apply settings without manually editing YAML files. This will create a new yaml file named eth1-net-config.yaml

sudo netplan set ethernets.eth1.addresses=["10.0.10.10/24"] --origin-hint eth1-net-config

Check changes:

netplan get

You'll see eth1 listed with the new static IP.

4. Add Gateway and DNS

sudo netplan set ethernets.eth1.gateway4="10.0.10.1" --origin-hint eth1-net-config
sudo netplan set ethernets.eth1.nameservers.addresses=["10.0.10.1"] --origin-hint eth1-net-config

Confirm configuration:

netplan get

5. Apply the Configuration

sudo netplan apply

Verify IPs:

ip a

eth1 will now show 10.0.10.10/24 as its assigned address.

The Results

• eth1 is now statically configured.
• Gateway and name servers are applied.
• The configuration is saved in a dedicated file (eth1-net-config.yaml).
• netplan get confirms all parameters are correctly indented and valid.

The Conclusion

Using netplan set and netplan get simplifies interface management—especially on servers with multiple NICs. Configurations are modular, clean, and easy to maintain. Static IPs are essential for service stability, and this method avoids manual YAML edits altogether.