Networking
Networking is one of those subjects that looks tidy in a diagram and immediately gets more interesting when real equipment, old decisions, multiple providers, firewalls, tunnels, and users are involved.
I learned a lot of this by building networks, breaking them, tracing packets, staring at routing tables, and eventually working with hosting and data-center infrastructure where "just reboot the router" is not a serious troubleshooting plan. The pages here are my notes on the parts I keep using.
The basics I keep coming back to
Routing, tunnels, and getting traffic from here to there
Running real networks
- Network design
- Data-center networking
- ISP and hosting networks
- Network security
- Wireless networking
- Monitoring and observability
- Troubleshooting
- Network automation
Labs, references, and things I built
- Building a networking homelab
- Network command reference
- Subnet calculator
- Cisco configuration generator
- Projects and case studies
My usual troubleshooting method is not very exciting: prove what works, follow the path, and stop guessing. Check link state, ARP/ND, routes, ACLs, NAT, DNS, counters, and captures in roughly that order. Packets are usually more honest than assumptions.
Last Modified: September 23, 2026, 2:28 pm