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Post Mortem

Code Orange: Fail Small is complete. The result is a stronger Cloudflare network

We have completed a massive engineering effort to make our infrastructure more resilient. Through new tools like Snapstone and the Engineering Codex, we've implemented safer configuration changes and automated best practices to prevent future incidents.

Route leak incident on January 22, 2026

An automated routing policy configuration error caused us to leak some Border Gateway Protocol prefixes unintentionally from a router at our Miami data center. We discuss the impact and the changes we are implementing as a result.

What came first: the CNAME or the A record?

A recent change to 1.1.1.1 accidentally altered the order of CNAME records in DNS responses, breaking resolution for some clients. This post explores the technical root cause, examines the source code of affected resolvers, and dives into the inherent ambiguities of the DNS RFCs.

Cloudflare outage on December 5, 2025

Cloudflare experienced a significant traffic outage on December 5, 2025, starting approximately at 8:47 UTC. The incident lasted approximately 25 minutes before resolution. We are sorry for the impact that it caused to our customers and the Internet. The incident was not caused by an attack and was due to configuration changes being applied to attempt to mitigate a recent industry-wide vulnerability impacting React Server Components.

Cloudflare outage on November 18, 2025

Cloudflare suffered a service outage on November 18, 2025. The outage was triggered by a bug in generation logic for a Bot Management feature file causing many Cloudflare services to be affected.

Cloudflare outage on November 18, 2025

Cloudflare suffered a service outage on November 18, 2025. The outage was triggered by a bug in generation logic for a Bot Management feature file causing many Cloudflare services to be affected.

Cloudflare incident on March 21, 2025

On March 21, 2025, multiple Cloudflare services, including R2 object storage experienced an elevated rate of error responses. Here’s what caused the incident, the impact, and how we are making sure it