The Internet is a cooperative system: CNAME to Dyn DNS outage of 6 July 2015
Jul 6, 2015Ryan Lackey
Summary
This post details an outage caused by an upstream DNS provider (Dyn) experiencing configuration issues, which impacted Cloudflare customers using CNAME records. Cloudflare engineers identified the issue by observing CNAME-based sites being affected, while domains hosted entirely on Cloudflare or external sites remained unaffected. The company collaborated with Dyn to resolve the issue and implemented temporary workarounds on their side.
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