Cheatsheets

networking/

• BSD Network Tools Inspecting and configuring networking on FreeBSD, OpenBSD, and NetBSD with ifconfig, route, netstat, and pf.
• Consul Service mesh and service discovery platform providing service registration, health checking, and distributed key/value storage.
• DNS Troubleshooting Diagnosing name resolution with dig, drill, host, and resolvectl: record types, CNAME chains, TTLs, authoritative vs recursive, DNSSEC, split-horizon, and common failure modes.
• Envoy Proxy Comprehensive guide to Envoy, a high-performance L7 proxy and communication bus for microservices.
• HAProxy High-performance TCP/HTTP load balancer and reverse proxy for distributing traffic across multiple servers.
• iptables/nftables Linux kernel firewall frameworks for packet filtering, NAT, and network traffic control.
• Istio Service Mesh Comprehensive guide to Istio service mesh for traffic management, security, and observability.
• Linux Network Tools Inspecting and configuring Linux host networking with iproute2 (ip, ss), tc, and friends.
• macOS Network Tools Inspecting and configuring networking on macOS with networksetup, scutil, ifconfig, pfctl, and the unified diagnostics tools.
• Nginx High-performance HTTP server and reverse proxy with load balancing, caching, and SSL termination capabilities.
• SSH & SSH Config Client-side SSH for daily SRE work: ~/.ssh/config, keys and agents, ProxyJump and bastions, local/remote/dynamic port forwarding, agent-forwarding risks, and SSH certificates.
• tcpdump/Wireshark Command-line and GUI tools for network packet capture and protocol analysis.