Tutorials
Brownout, Not Blackout: Multi-WAN Failover Tests That Matter
Test multi-WAN behavior when a link stays up but latency, loss, DNS or application reachability degrades. Measure detection, new connections, existing sessions and failback as separate outcomes.
Secure A LAN Model Server: Ollama And LM Studio Across VLANs
Define allowed clients, authentication and resource limits before exposing Ollama or LM Studio across VLANs. Evaluate each product's controls separately and check that direct backend access cannot bypass the intended path.
Your Network Configuration Is A Security Log
Use preserved configuration exports and normalized comparisons to detect changes in network access, routing and logging. Correlate differences with identity and runtime evidence; a clean diff does not prove a clean device.
SD-WAN Assurance: What to Monitor Before Blaming the ISP
An SD-WAN assurance runbook for separating ISP, underlay, overlay, policy, DNS, SaaS, and application problems before escalating.
Can a Local Coding Model Run an Agent? Test Tools, Patches, and Safety
Use a disposable repository to test a self-hosted coding model's API, tool calls, patch quality, refusal boundaries, and rollback before giving it real code.
Local LLMs in the Codex App: OpenCodex Setup and Privacy Limits
Compare the native Codex CLI local-model path with OpenCodex's third-party proxy for the desktop app. Verify actual routing, hosted sidecars and recovery before treating a local model as a private workflow.
Why Port Forwarding Fails: Diagnose Double NAT, CGNAT, and IPv6 Before Buying Gear
A topology-first troubleshooting guide for failed port forwards: public IP checks, double NAT, CGNAT, IPv6 firewall rules, UPnP, VPN, and tunnel alternatives.
Stop Binding Paid Wi-Fi Time To A Phone MAC Address
Design paid Wi-Fi access around recoverable vouchers or accounts rather than a phone's observed MAC address. Check private-address behavior, purchase recovery and duplicate-credit prevention on the actual devices and portal.
EVPN/VXLAN Lab First: Build a Cisco IOS XE Fabric Before Touching Production
Plan EVPN/VXLAN tests only after confirming the exact Cisco platform and image support the required features. Validate underlay, overlay and denied paths separately, with representative hardware checks before production.
From Digital Twin to Change Window: A Safe Network CI/CD Workflow
A network CI/CD workflow showing how to move from intent and digital twin validation to reviewed change windows, rollback, and post-change evidence.