How to Set up a Static IP address on Ubuntu 26.04

Gather your network details first

Collect these numbers before you edit any file. Guessed values are the most common reason a static setup breaks the connection.

1. Find your current address and interface name. Open a terminal and run ip -br addr. Find the interface that holds your current address. Its name usually looks like ens18, enp3s0, or eth0. Write down the interface name and the address, including the number after the slash. That number is the prefix, explained in the tip below., such as 192.168.1.45/24.
   

   💡TipThe /24 at the end is a subnet mask in CIDR notation (a shorthand that shows how much of the address identifies the network).

   Most home networks use /24.

2. Find your gateway. The gateway is your router, the device that sends your traffic to the internet. Run ip route | grep default. The address after via is your gateway, such as 192.168.1.1.
3. Pick an address outside the router’s DHCP pool. DHCP (the system that hands out addresses automatically) reserves a range of addresses for itself. Log in to your router’s admin page and check that range. Choose an unused address outside it, like 192.168.1.50.
   

   Warning: If another device already uses your chosen address, you get an address conflict. Both devices may drop off the network, and the cause is hard to trace. Check first by running ping 192.168.1.50 from another computer. No reply means the address is probably free.

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Write the Netplan configuration

Netplan reads YAML files (a text format that depends on indentation) from /etc/netplan/. One wrong space stops the whole file from loading. Editing files in this folder requires administrator privileges, so use sudo (a command that runs another command with administrator rights).

1. Open the existing Netplan file. List the folder contents with ls /etc/netplan/. You likely see a file such as 50-cloud-init.yaml or 00-installer-config.yaml. Open it with sudo nano /etc/netplan/50-cloud-init.yaml, using the filename you see.
   

   💡TipBack up the file before you edit it so you can restore it if something goes wrong: sudo cp /etc/netplan/50-cloud-init.yaml ~/netplan-backup.yaml.
2. Replace the contents with your static settings. Netplan tabs are not accepted. Indent with spaces only, and keep each level exactly two spaces deeper than the one above it. The example below uses the values from the previous section. Swap in your own interface name, address, gateway, and DNS servers.
   

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   network:
     version: 2
     ethernets:
       ens18:
         dhcp4: false
         addresses:
           - 192.168.1.50/24
         routes:
           - to: default
             via: 192.168.1.1
         nameservers:
           addresses: 

   This configuration turns off DHCP for the interface and assigns the fixed address. It sends outside traffic through your router and sets the DNS servers. (the services that turn names like example.com into addresses). Your router works as a first DNS server. Add a public one as a backup in case the router stops answering.

3. Save the file and restrict its permissions. The steps below use nano, a text editor that runs in the terminal, and its save and exit keys. In nano, press Ctrl+O, then Enter to save, and Ctrl+X to exit. Then run sudo chmod 600 /etc/netplan/50-cloud-init.yaml (this requires administrator privileges).
   

   Tip: Netplan warns you when every user on the system can read the file. Setting it to 600 removes the warning and keeps the file private.

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Stop cloud-init from overwriting your changes

Many Ubuntu installs use cloud-init (a tool that configures the system on first boot). On those systems, cloud-init can regenerate the network settings and switch DHCP back on. This step prevents that. It requires administrator privileges. It does no harm if cloud-init is not installed.

1. Tell cloud-init to leave networking alone. Create a new file with sudo nano /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg. Add this single line:
   

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   network: {config: disabled}

2. Save and close the file.

Test the configuration before you commit

A mistake in the file can cut off your connection, and you may not be able to reconnect over the network. Test the changes before you make them permanent.

1. Check the syntax. Run sudo netplan generate. No output means the file is valid. An error message usually names the line number. Indentation is the most common cause.
2. Apply the settings with a safety net. Run sudo netplan try (this requires administrator privileges). Netplan applies the new configuration and waits for your confirmation. Before you run this step, make sure you have a local console or a session you can afford to lose. If you connect over SSH (a tool for logging in to a computer remotely) and the new address is wrong, you may need physical access to fix it. Press Enter to keep the settings. If you don't confirm within about two minutes, or your connection drops, Netplan rolls back to the previous settings automatically.
3. Make it permanent. After the test passes, run sudo netplan apply (this requires administrator privileges). This applies the configuration and keeps it through reboots.

Verify the new address works

Confirm that the settings took effect, both on the machine and from the rest of your network.

1. Check the address on the machine. Run ip -br addr show ens18, replacing the interface name with yours. Your fixed address appears, and the old address that DHCP (automatic address assignment) gave the machine is gone.
2. Check the route and internet access. Run ip route to confirm that traffic leaves through your gateway (the default route, the path used for any address outside your network). Run ping -c 4 1.1.1.1 to test internet connectivity, then ping -c 4 ubuntu.com to test DNS.
   

   Tip: If the IP test works but the name test fails, the problem is DNS. Your static address is fine. Check the nameservers block in your YAML file.

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3. Connect from another computer. On your Windows PC, open PowerShell and run ping 192.168.1.50, using your address. Replies confirm that other devices can reach the server at its new address.

Set a static IP on Ubuntu Desktop instead

Ubuntu Desktop uses NetworkManager (the service that manages network connections on desktop systems). You set a fixed address through the interface and skip the YAML file.

1. Open the network settings. Click the system menu in the top-right corner, then the gear icon next to your connection. Alternatively, open Settings and choose Network.
2. Edit the connection. Click the gear icon beside your active wired or Wi-Fi connection. Go to the IPv4 tab and change IPv4 Method from Automatic (DHCP) to Manual.
3. Enter your values. Under Addresses, enter your chosen IP, the netmask (for example, 255.255.255.0 for a /24 network), and the gateway. Under DNS, enter your DNS servers separated by commas. Click Apply. Save your work before you click Apply. Turning the connection off drops any remote session, so keep this in mind before you start. Then turn the connection off and on again.

Troubleshoot common problems

These checks fix most failures.

• Read the Netplan error. Run sudo netplan --debug apply to see the full output. Most failures come from bad indentation, a missing / before the prefix length, or the wrong interface name.
• Check the interface name. If the YAML refers to an interface that doesn't exist, the network never comes up. Run ip link and match the name exactly. Names are case-sensitive.
• Restore your backup if you lose access. From the console, run sudo cp ~/netplan-backup.yaml /etc/netplan/50-cloud-init.yaml, then sudo netplan apply.

What to do next

Write down your address, gateway, DNS settings, and the Netplan file location. You need them if a router reset or a new network card changes your setup. Also add a matching reservation in your router's DHCP table so the router never hands that address to another device. [192.168.1.1, 1.1.1.1]