Add incident review for the July 2026 live clinic gateway failure - #173
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First document in docs/incidents/. Covers the first production use of the gateway imaging flow (6-7 July): three stacked faults with one identical symptom - a private DNS blackhole via a broken-but-Approved workers, and a zombie relay listener - private endpoint, the asyncio websockets client failing under gevent plus what was done, the improvements that followed (phase-tagged error reporting, runbooks, echo probe, end-to-end test participant, healthcheck and per-site toggle work), and the learnings.
steventux
approved these changes
Jul 27, 2026
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First document in docs/incidents/. Covers the first production use of the gateway imaging flow (6-7 July): three stacked faults with one identical symptom - a private DNS blackhole via a broken-but-Approved workers, and a zombie relay listener - private endpoint, the asyncio websockets client failing under gevent plus what was done, the improvements that followed (phase-tagged error reporting, runbooks, echo probe, end-to-end test participant, healthcheck and per-site toggle work), and the learnings.
Jira link
https://nhsd-jira.digital.nhs.uk/browse/DTOSS-13337