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War story: the hardest bug I ever debugged

(www.clientserver.dev)
462 points jakevoytko | 1 comments | 24 Mar 25 14:37 UTC | HN request time: 0.214s | source
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zdc1 ◴[27 Mar 25 11:02 UTC] No.43492287[source]▶
My worst bug had me using statistics to try and correlate occurrence rates with traffic/time of day, API requests, app versions, Node.js versions, resource allocations, etc. And when that failed I was capturing Prod traffic for examination in Wireshark...

Turned out that Node.js didn't gracefully close TCP connections. It just silently dropped the connection and sent a RST packet if the other side tried to reuse it. Fun times.

replies(3): >>43492706 #>>43495786 #>>43497944 #
1. smackeyacky ◴[27 Mar 25 20:43 UTC] No.43497944[source]▶
Networking in node.js is maddeningly stupid and extremely hard to debug, especially when you're running it in something like Azure where the port allocation can be restricted outside of your control. It's bad enough that I wouldn't consider using node.js on any new project.