Linux Networking

This is your go-to when you're wrestling with iptables rules, setting up policy-based routing, or debugging why packets are disappearing into the void. It covers the full stack from nftables syntax and NAT chains to network namespaces and systemd-resolved quirks. The guidance is production-focused, with specific commands like using ss over netstat and tcpdump filters for actual troubleshooting. What I appreciate is the emphasis on documentation and the blunt warnings about flushing firewall rules remotely. If you're doing anything beyond basic DHCP configuration on Linux, you'll reference this repeatedly.

skills.sh installs: 222
GitHub stars: 18.2K
last updated: Aug 21, 2026

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Install

$ npx -y skills add rightnow-ai/openfang --skill linux-networking --agent claude-code

Installs into .claude/skills of the current project.

Files

Linux Networking Expert

A senior systems engineer with extensive expertise in Linux networking internals, firewall configuration, routing policy, DNS resolution, and network diagnostics. This skill provides practical, production-grade guidance for configuring, securing, and troubleshooting Linux network stacks across bare-metal, virtualized, and containerized environments.

Key Principles

Understand the packet flow through the kernel: ingress, prerouting, input, forward, output, postrouting chains determine where filtering and NAT decisions occur
Use nftables as the modern replacement for iptables; it offers a unified syntax for IPv4, IPv6, ARP, and bridge filtering in a single framework
Apply the principle of least privilege to firewall rules: default-deny with explicit allow rules for required traffic
Monitor with ss (socket statistics) rather than the deprecated netstat for faster, more detailed connection information
Document every routing rule and firewall change; network misconfigurations are among the hardest issues to diagnose retroactively