Network Configuration for ARM SBCs

Network configuration for ARM single-board computers

Summary

This guide covers practical network configuration for ARM-based single-board computers running Linux, including the LeMaker Banana Pi, Banana Pro, and Guitar. It walks through Ethernet and WiFi setup, DNS configuration, basic firewall rules, SSH remote access, and common troubleshooting steps. The instructions apply to Debian-based distributions (Ubuntu, Armbian) and can be adapted for other Linux distributions with minor changes.

Who This Is For

Users who have completed initial board setup and need to configure reliable network connectivity. Basic familiarity with the Linux command line and a text editor such as nano is assumed.

Ethernet Setup

DHCP (Default)

Most LeMaker OS images configure Ethernet for DHCP by default. After connecting an Ethernet cable and booting, the board should receive an IP address automatically. Verify with ip addr show eth0.

Static IP

To assign a static IP, edit the appropriate configuration file for your distribution:

  • /etc/network/interfaces (ifupdown): Set iface eth0 inet static with address, netmask, gateway, and dns-nameservers fields. Restart networking with sudo systemctl restart networking.
  • Netplan (Ubuntu 18.04+): Edit /etc/netplan/01-netcfg.yaml, set dhcp4: false, and add addresses, gateway4, and nameservers entries. Apply with sudo netplan apply.

WiFi Configuration

Boards with onboard WiFi (Banana Pro) or a USB WiFi adapter can connect wirelessly using one of two methods:

  • wpa_supplicant: Create or edit /etc/wpa_supplicant/wpa_supplicant.conf with your SSID and passphrase. Use wpa_passphrase "YourSSID" "YourPassword" | sudo tee /etc/wpa_supplicant/wpa_supplicant.conf to generate an encrypted entry. Restart the interface with sudo ifdown wlan0 && sudo ifup wlan0.
  • NetworkManager: If your image uses NetworkManager, connect with nmcli device wifi connect "YourSSID" password "YourPassword". List available networks with nmcli device wifi list.

DNS Configuration

DNS servers are typically set via DHCP or in the network configuration files described above. To override manually, edit /etc/resolv.conf and add nameserver 8.8.8.8 and nameserver 1.1.1.1. On systems using systemd-resolved, configure DNS in /etc/systemd/resolved.conf and restart the service.

Firewall Basics with UFW

The Uncomplicated Firewall (ufw) provides a simple interface for managing iptables rules:

  1. Install: sudo apt install ufw
  2. Allow SSH: sudo ufw allow ssh
  3. Enable: sudo ufw enable
  4. Check status: sudo ufw status verbose

Add additional rules as needed — for example, sudo ufw allow 80/tcp to permit HTTP traffic.

SSH Remote Access

SSH is the primary method for managing headless SBCs. Ensure the SSH server is running with sudo systemctl status ssh. For security, disable password authentication and use key-based login. Copy your public key with ssh-copy-id user@board-ip, then set PasswordAuthentication no in /etc/ssh/sshd_config and restart the service.

Monitoring Network Status

Useful commands for diagnosing network health:

  • ip addr — show interface addresses
  • ip route — display routing table
  • ping -c 4 8.8.8.8 — test Internet reachability
  • ping -c 4 google.com — test DNS resolution
  • ss -tulnp — list listening ports

Troubleshooting

  • No link light on Ethernet port: Try a different cable. Check that the router port is active. Some boards require a specific kernel module — verify with dmesg | grep eth.
  • DHCP failure: Confirm the DHCP server is running on your network. Release and renew manually: sudo dhclient -r eth0 && sudo dhclient eth0.
  • DNS not resolving: Test with nslookup google.com 8.8.8.8. If that works, the issue is with your configured DNS servers, not connectivity.
  • Slow network speeds: Check for duplex mismatch with ethtool eth0. Ensure the Ethernet cable supports the required speed rating. On WiFi, check signal strength with iwconfig.

FAQ

  • Can I use both Ethernet and WiFi at the same time? Yes, but ensure your routing table is correct so traffic uses the intended interface. Set metric values in your network configuration to prioritize one interface.
  • How do I find my board's IP address without a display? Check your router's DHCP leases, or scan the local subnet with nmap -sn 192.168.1.0/24.
  • Should I use a static IP or DHCP? For headless servers, a static IP or a DHCP reservation is recommended so the address does not change between reboots.

Related Guides

Author: LeMaker Documentation Team
Last updated: 2026-02-10