Sometimes it is the network: a war story
A sysadmin describes troubleshooting a mysterious DNS timeout issue affecting a single development machine, which ultimately traced back to an intermittent network problem—specifically, a faulty ethernet cable causing occasional packet loss. The post highlights how even experienced administrators can overlook basic network issues when symptoms point elsewhere.
Background
- Chris Siebenmann is a Unix sysadmin and blogger at the University of Toronto, known for clear, practical takes on system administration.
- This post is a "war story" — a common genre in sysadmin circles where someone recounts a painful real-world debugging episode.
- The title refers to a running joke in IT: when something breaks, people often blame "the network" first. The phrase "sometimes it is the network" pushes back on that stereotype, acknowledging that network problems do happen — but are often hard to find because diagnostic tools can be misleading.
- The piece illustrates how a subtle network issue (e.g. packet loss, misconfigured switches, or routing asymmetry) can masquerade as an application or server problem, and how tricky it is to prove the root cause.