Today we mitigated 1.1.1.1

On May 31, 2018, Cloudflare experienced a 17-minute outage on its 1.1.1.1 resolver service due to an oversight in the Gatebot DDoS mitigation pipeline. The issue occurred when new code was deployed that integrated with Provision API but failed to account for special IP ranges used by Cloudflare's recursive DNS resolver. As a result, the systems interpreted the resolver traffic as an attack and automatically deployed DNS mitigations, rendering 1.1.1.1 inaccessible globally. The company is using this incident to improve its internal systems and apologizes for any inconvenience caused to customers.