Wi-Fi from the Linux terminal: nmcli essentials

Wi‑Fi from the Linux terminal: nmcli essentials

Tags: Linux, Networking

Intro – what, why, and who this is for

Linux ships with NetworkManager, and its command‑line client nmcli lets you manage Wi‑Fi without ever touching a GUI.

• What: A step‑by‑step guide to scan for networks, connect to one, and spin up a hotspot—all from the terminal.
• Why: Handy on headless servers, minimal desktop environments, or when you need a quick fix while troubleshooting.
• Who: Beginners who have a working Linux install and a wireless interface (e.g., wlan0), and intermediate users who want a repeatable scriptable workflow.

You only need five commands, plus a couple of optional flags for passwords and device names. Grab a terminal, and let’s get the radio talking.

Part 1 – Understanding the wireless device

Tip: If nmcli device status reports unavailable or disconnected, make sure the wireless card isn’t blocked (rfkill list) and that the driver is loaded (lsmod | grep iwlwifi for Intel, lsmod | grep ath9k for Atheros, etc.).

Part 2 – Scanning for Wi‑Fi networks

The scan command is a single line, but you’ll often want a tidy list of SSIDs, signal strength, and security type.

# Scan and show a compact table
nmcli -f SSID,SIGNAL,SECURITY device wifi list

You can filter the output with grep or awk if you’re looking for a specific network:

nmcli -f SSID,SIGNAL,SECURITY device wifi list | grep -i "cafe"

Part 3 – Connecting to a Wi‑Fi network

3.1 One‑liner for a known password

nmcli device wifi connect "MyHome" password "superSecret123"

• device wifi connect tells NetworkManager to create a new connection profile (or reuse an existing one).
• If the SSID is hidden, add --hidden yes:

nmcli device wifi connect "HiddenNet" password "p@ssw0rd" --hidden yes

3.2 Re‑using a saved profile

If you’ve connected before, the profile already exists. To reconnect without re‑entering the password:

nmcli connection up "MyHome"

You can list saved Wi‑Fi profiles with:

nmcli connection show --active
nmcli connection show

The first shows what’s currently active, the second lists all saved connections.

Part 4 – Creating a Wi‑Fi hotspot (AP mode)

A hotspot turns your Linux box into a wireless router. The command below creates a temporary hotspot called MyHotspot with password hotspot123. It works on most modern Wi‑Fi chips that support AP mode.

nmcli device wifi hotspot ifname wlan0 ssid MyHotspot password hotspot123

• ifname forces the command to use a specific interface (useful when you have more than one wireless device).
• The hotspot will stay up until you run nmcli connection down MyHotspot or reboot.

You can inspect the hotspot’s settings with:

nmcli connection show MyHotspot

Part 5 – Summarizing the five essential commands

Memorize these five lines, and you have a complete Wi‑Fi toolbox.

Hands‑on example (full, copy‑and‑paste script)

#!/usr/bin/env bash
# wifi-demo.sh – demonstrates the 5‑command workflow
# Run as a normal user; sudo is not required if you belong to the "netdev" group.

# 1️⃣ Show device status
echo "=== Device status ==="
nmcli device status

# 2️⃣ Scan for networks (filter for "Office")
echo -e "\n=== Scan for 'Office' networks ==="
nmcli -f SSID,SIGNAL,SECURITY device wifi list | grep -i "Office"

# 3️⃣ Connect (replace with your own SSID/password)
SSID="OfficeNet"
PASS="officePass42"
echo -e "\n=== Connecting to $SSID ==="
nmcli device wifi connect "$SSID" password "$PASS"

# 4️⃣ Verify connection
echo -e "\n=== Active connections ==="
nmcli connection show --active

# 5️⃣ Create a hotspot named "DemoAP"
HOTSPOT_SSID="DemoAP"
HOTSPOT_PASS="demo12345"
IFACE=$(nmcli -t -f DEVICE,TYPE device status | grep ':wifi' | cut -d: -f1 | head -n1)

echo -e "\n=== Starting hotspot $HOTSPOT_SSID on $IFACE ==="
nmcli device wifi hotspot ifname "$IFACE" ssid "$HOTSPOT_SSID" password "$HOTSPOT_PASS"

# Show hotspot details
echo -e "\n=== Hotspot details ==="
nmcli connection show "$HOTSPOT_SSID"

How to run

chmod +x wifi-demo.sh
./wifi-demo.sh

The script prints each step, connects to the network you specify, and finally creates a hotspot. Adjust SSID, PASS, HOTSPOT_SSID, and HOTSPOT_PASS to match your environment.

Common mistakes & troubleshooting

Try it yourself

1. Turn off any GUI network manager (if running) with sudo systemctl stop NetworkManager only if you want to test nmcli in isolation.
2. Use nmcli device wifi list to locate a network you have never connected to before.
3. Connect to it without storing the password (--ask flag) to see the interactive prompt:

nmcli device wifi connect "<NEW_SSID>" --ask

Did it work? If not, note the error and refer to the table above.

What’s next

• Scripted auto‑reconnect: Use a cron job or systemd service that runs nmcli connection up <profile> when the link drops.
• Advanced security: Switch to WPA3 (--wifi-sec wpa3) and store passwords in the keyring instead of plain text.
• Multi‑SSID hotspot: Create a bridge (br0) to share both Ethernet and Wi‑Fi while keeping the same SSID for roaming.
• NetworkManager D‑bus: Control Wi‑Fi from Python or Go for custom dashboards.

Bookmark this page for a quick terminal‑only Wi‑Fi cheat sheet.