Field Notes
Field notes from the operator's seat.
Network engineering, automation, and the plumbing of the internet — explained by tracing real systems rather than reciting theory. Written for engineers who like to see the packets.
Source NAT on the SRX: Anatomy of a Silent Failure
How source NAT works on Junos SRX, how to read the session table like an operator, and the re-IP failure mode that produces zero errors, zero logs, and misleading test results.
Read the article →Trace a Website to the Edge of the Internet
Using only dig, curl, and traceroute, follow one web request from a laptop to the machine that answers it — and learn anycast, CDN caching, and BGP by watching real systems work.
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