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How to View and Configure Network Interfaces in Linux

Published 1 November 2025

If you use Linux, whether you’re running a web server, a desktop, or just tinkering with a Raspberry Pi, you’ll eventually need to deal with networking. Maybe you want to check your IP address, set up a static IP for a home server, or troubleshoot a flaky Wi-Fi connection. Whatever your task, knowing how to view and configure network interfaces is a fundamental Linux skill.

Unlike some operating systems that hide networking behind layers of menus, Linux gives you direct access to see exactly what’s happening under the hood. With just a few commands, you can list every interface, check or change your IP addresses, manage Wi-Fi, enable or disable connections, and diagnose problems. Mastering these basics not only makes you self-reliant, but also unlocks the full potential of your Linux machine.

This guide will walk you through everything you need to know, from understanding what a network interface is to step-by-step instructions for viewing and configuring both wired and wireless networks. Real-world examples and troubleshooting tips are included, so you’re ready for anything.

What Are Network Interfaces in Linux?

A network interface is any point where your Linux system connects to a network. This could mean a physical Ethernet port, a Wi-Fi card, a USB Internet dongle, or even a virtual device used for VPNs or containers. Each interface acts like a doorway for your device’s network traffic.

Common interface names:

eth0, enp2s0, eno1: Wired Ethernet interfaces.
wlan0, wlp3s0: Wi-Fi interfaces.
lo: The “loopback” interface (your local system, always 127.0.0.1).
tun0, tap0: VPN or virtual interfaces.

Interfaces get their names based on hardware, Linux version, and distribution. Newer systems use longer, more descriptive names, while older ones often use the simple eth0/wlan0 style.

Why You Need to View and Configure Network Interfaces

Here’s why this skill matters:

Troubleshooting: Quickly see if your connection is up or down.
Customization: Set a static IP for a server or a device on your home network.
Security: Disable unused interfaces or monitor suspicious ones.
Performance: Adjust settings for better speed, lower latency, or specific network needs.
Remote access: Configure a machine for SSH, VPN, or remote desktop.

Even if you mostly use graphical tools, knowing the basics at the terminal helps when things go wrong or when you’re managing servers without a GUI.

Listing Network Interfaces: The Most Common Tools

Let’s start by discovering what interfaces your system actually has. There are several ways to do this, and which you use often comes down to preference or what’s available.

Using the ip Command (Modern and Recommended)

The ip command is the standard for modern Linux networking.

List all interfaces:

ip link show

or, for short:

ip a

You’ll get output like:

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 ... 2: enp2s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 ... 3: wlp3s0: <BROADCAST,MULTICAST> mtu 1500 ...

Using ifconfig (Older but Still Widely Used)

Ifconfig is still common, though it’s technically deprecated.

Show all interfaces:

ifconfig -a

If you get a “command not found” error, you can install it:

sudo apt install net-tools

Using nmcli (For NetworkManager-Controlled Systems)

On desktops and laptops, NetworkManager is the background tool managing connections.

List interfaces:

nmcli device status

You’ll see a table with device names and their state (connected, disconnected, etc.)

Using Graphical Tools

If you have a desktop environment:

GNOME: Open “Settings” > “Network”
KDE: Use “System Settings” > “Network”
XFCE: “Settings” > “Network Connections”

You’ll see wired, wireless, and VPN interfaces, with status and configuration options.

Understanding Network Interface Details

Each interface entry shows a lot of information. Here’s what to look for:

Interface name: (e.g., enp2s0, wlp3s0)
State: UP (enabled), DOWN (disabled)
MAC address: The unique hardware address (looks like 12:34:56:78:9a:bc)
IPv4/IPv6 addresses: Assigned addresses (e.g., 192.168.1.100)
MTU: Maximum Transmission Unit, usually 1500 for Ethernet
Flags: (e.g., BROADCAST, MULTICAST, RUNNING)

Understanding these can help you diagnose issues or configure your network for specific needs.

Checking Your IP Address and Connection Status

Finding your IP address is one of the most common networking tasks.

Show all IP addresses:

ip addr show

ip a

Look for the inet line under the interface you’re interested in:

2: enp2s0: <...>     inet 192.168.1.100/24 brd 192.168.1.255 scope global dynamic enp2s0

Here, 192.168.1.100 is your IP.

Check all IPv4 addresses only:

hostname -I

For wireless:

iwconfig

(If not installed, try: sudo apt install wireless-tools)

Check connection status:

nmcli device status

Loopback (your own machine): Always has IP 127.0.0.1 assigned to lo.

Configuring Network Interfaces

Configuring interfaces can mean enabling/disabling them, changing IP settings, or setting up advanced options. On Linux, you can do this live (changes last until reboot) or make them permanent (changes survive restarts).

Enabling and Disabling Interfaces

Bring an interface up (enable):

sudo ip link set enp2s0 up

Bring an interface down (disable):

sudo ip link set enp2s0 down

With ifconfig:

sudo ifconfig enp2s0 up

sudo ifconfig enp2s0 down

With nmcli:

nmcli device connect enp2s0

nmcli device disconnect enp2s0

Setting a Static IP Address (Temporarily)

With ip (until reboot):

sudo ip addr add 192.168.1.55/24 dev enp2s0

sudo ip route add default via 192.168.1.1

With ifconfig:

sudo ifconfig enp2s0 192.168.1.55 netmask 255.255.255.0

sudo route add default gw 192.168.1.1 enp2s0

Switching to DHCP (Get IP Automatically)

With dhclient:

sudo dhclient enp2s0

With nmcli:

nmcli con mod "Wired connection 1" ipv4.method auto

nmcli con up "Wired connection 1"

Configuring DNS Servers

Temporary (until reboot): Edit /etc/resolv.conf and add:

nameserver 8.8.8.8

nameserver 1.1.1.1

Permanent: Set through your network manager or edit the relevant config files for your distro.

Wireless Network Configuration

List available Wi-Fi networks:

nmcli device wifi list

Connect to a network:

nmcli device wifi connect "NetworkName" password "YourPassword"

Disconnect:

nmcli device disconnect wlp3s0

Replace wlp3s0 with your actual Wi-Fi device name.

Saving and Applying Network Changes

Live changes using ip or ifconfig are not persistent. After a reboot, settings revert.

To make permanent changes, edit configuration files or use your network manager’s “Edit Connections” dialog.

For most modern distros, NetworkManager or netplan (on Ubuntu) manages configs.

Example: Ubuntu with Netplan

Edit /etc/netplan/01-netcfg.yaml (or similar):

network:
  version: 2
  renderer: NetworkManager
  ethernets:
    enp2s0:
      dhcp4: no
      addresses: [192.168.1.55/24]
      gateway4: 192.168.1.1
      nameservers:
        addresses: [8.8.8.8,1.1.1.1]

After editing, apply with:

sudo netplan apply

On older systems, edit /etc/network/interfaces.

On Red Hat/CentOS/Fedora, use /etc/sysconfig/network-scripts/ifcfg-INTERFACE.

Troubleshooting Common Network Issues

My interface is missing or shows DOWN

Check for hardware problems: try unplugging/replugging cables, rebooting, or checking dmesg for errors.
Make sure the driver is loaded (lspci -k or lsusb).
Bring the interface up with sudo ip link set INTERFACE up.

I can’t get an IP address

Try restarting the DHCP client: sudo dhclient INTERFACE.
Check your router or DHCP server.
Inspect /etc/network/interfaces or netplan files for errors.

My changes disappear after reboot

Make sure you edited the correct config file for your distro.
For temporary changes, remember they won’t persist—make them permanent if needed.

Wi-Fi doesn’t work

Check if your wireless device is listed: ip link show or nmcli device status.
Try scanning for networks: nmcli device wifi list.
Verify your kernel has the right drivers. Use dmesg | grep firmware to spot missing firmware.

DNS problems

Try changing DNS servers in /etc/resolv.conf or through the network manager.
Test with ping 8.8.8.8 (Google DNS) and ping google.com to see if it’s a DNS or general network issue.

Real-World Scenarios and Tips

Assigning a Static IP for a Home Server

You want your Raspberry Pi to always have the same IP on your LAN, so you can SSH in reliably. Use netplan or network manager to set a static IP, specify a gateway, and set DNS servers.

Quickly Disabling Wi-Fi When Wired

Need to test if your Ethernet cable is working? Disable Wi-Fi:

nmcli device disconnect wlp3s0

Re-enable it later:

nmcli device connect wlp3s0

Checking Which Programs Use the Network

See which process is using each interface:

sudo lsof -i

Resetting a Stuck Network Connection

Restart network manager (for desktops):

sudo systemctl restart NetworkManager

Or reapply your Netplan config:

sudo netplan apply

Switching Between Multiple Networks

If you move your laptop between work and home, use:

nmcli connection show

nmcli connection up "Work Ethernet"

nmcli connection up "Home Wi-Fi"

Frequently Asked Questions (FAQ)

Q: Why do interface names look different on different systems?
A: Newer Linux uses “predictable” names (like enp2s0) based on hardware location. Older systems use eth0, wlan0. It’s mostly cosmetic, but you can change naming rules if you prefer the old style.
Q: How can I see which interface is connected to the internet?
A: Use ip route or route -n. The default route (0.0.0.0) points to your gateway, and the interface listed is your main connection.
Q: How do I set a static IP for Wi-Fi?
A: Use your network manager’s GUI, or edit the configuration as you would for Ethernet, specifying your wireless interface name.
Q: Can I have multiple active interfaces?
A: Yes, for example, you can use both Ethernet and Wi-Fi at once, but routing and priorities will affect which is used for outgoing traffic.
Q: How do I see my public IP address?
A: Use a service like: curl ifconfig.me

Conclusion

Networking doesn’t have to be intimidating on Linux. Once you know how to view, configure, and troubleshoot your interfaces, you’re empowered to handle everything from basic connectivity to advanced server setups. Whether you prefer a quick terminal command or a friendly GUI, Linux gives you the tools to stay in control.

Practice listing your interfaces, experiment with enabling/disabling them, and don’t be afraid to modify configurations as you learn. Save your changes carefully, keep a backup of config files, and remember—if something goes wrong, there’s almost always a way to fix it without reinstalling or rebooting.

With experience, you’ll find that network management becomes second nature. And whenever you’re stuck, the Linux community is just a forum post or chat away, ready to help you get connected.

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