One Abuse Complaint Later: Hardening a Home Proxy Without Blocking All UDP

This story was originally published on HackerNoon at: https://hackernoon.com/one-abuse-complaint-later-hardening-a-home-proxy-without-blocking-all-udp.
A home proxy exit survived its first abuse complaint. Selective discovery filters preserve calls; controlled tests and rollback checks expose their limits.
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- A shared self-hosted proxy exit earned its first abuse complaint 40 minutes after a torrent client appeared on the network. The hoster's policy was one page long: second complaint, IP null-routed. - Blocking UDP disrupted messenger calls while text messages still worked. WhatsApp survived through TCP fallback, but that did not make the blanket block a usable policy. - The working strategy cuts common peer discovery instead of transport: tracker domains, four DHT bootstrap hostnames, a protocol sniffer with documented limits, and the classic port range. Warm caches survive it, and the article says where. - The same box runs two transports, because the TCP and XHTTP paths behaved differently on some mobile networks I tested; I did not determine why. - The rule installer avoids duplicate rules. The database updater adds validation and attempts rollback; neither property makes it a complete abuse-prevention system. - A later slowdown exposed buffers retained by a separate WARP process. A closed TCP state did not mean its descriptors and memory had been released.