linux-networking

Purpose

This skill handles Linux networking tasks, including IP configuration with Netplan, firewall management via UFW or Nftables, DNS setup, VPN configuration for Wireguard or Tailscale, and inter-instance routing on systems like System76.

When to Use

Use this skill for server setup on Ubuntu/Debian systems, securing applications with firewalls, establishing secure remote access via VPN, resolving DNS issues in containerized environments, or optimizing routing between networked instances in data centers or edge devices.

Key Capabilities

• Configure static/dynamic IP addresses using Netplan YAML files (e.g., set interface to DHCP or static IP).
• Manage firewalls with UFW for simple rules (e.g., allow/deny ports) or Nftables for advanced packet filtering via tables and chains.
• Handle DNS resolution with tools like systemd-resolved or /etc/resolv.conf edits.
• Set up VPNs: Wireguard for peer-to-peer tunnels using wg-quick, or Tailscale for automatic mesh networks with key authentication.
• Implement inter-instance routing on System76 hardware, such as setting up OSPF or static routes for multi-device communication.

Usage Patterns

Always run commands with sudo for root privileges. For scripts, check if services like NetworkManager or systemd-networkd are active. Use environment variables for sensitive data, e.g., export TAILSCALE_API_KEY=$SERVICE_API_KEY before Tailscale operations. In AI responses, structure tasks as sequential commands: first validate config files, then apply changes, and finally verify with diagnostic tools. For automation, wrap commands in bash scripts with error checks, e.g., use set -e to exit on failure.