The Time it Wasn't DNS

QCon San Francisco 2025

Session Incident Analysis

The Time it Wasn't DNS

Wednesday Nov 19 / 03:55PM PST, Seacliff ABC at Hyatt Regency, San Francisco

Abstract

In January of 2023, the Microsoft Azure Wide Area Network experienced a global outage. If you were a Microsoft customer at the time, you were impacted by this outage. Sean walks us through the numerous factors - events and conditions - that contributed to the outage and explains why it's not always DNS. (Spoiler: sometimes it's BGP)

Topics

Incident Analysis Learning from Incidents Incident Response
76% senior dev or higher
1:11 speaker ratio
60+ practitioners

QCon San Francisco 2025 is a three day conference for senior software engineers, architects and team leads. An international program committee of working engineers selects every session. Patterns and practices, not products and pitches.

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