Cloudflare 1.1.1.1 Incident on July 14, 2025

Summary

On 14 July 2025, Cloudflare's 1.1.1.1 Resolver service became unavailable to the Internet starting at 21:52 UTC and ending at 22:54 UTC. The majority of 1.1.1.1 users globally were affected. For many users, not being able to resolve names using the 1.1.1.1 Resolver meant that basically all Internet services were unavailable. This outage can be observed on Cloudflare Radar.The outage occurred because of a misconfiguration of legacy systems used to maintain the infrastructure that advertises Cloudflare’s IP addresses to the Internet.This was a global outage. During the outage, Cloudflare's 1.1.1.1 Resolver was unavailable worldwide.We’re very sorry for this outage. The root cause was an internal configuration error and not the result of an attack or a BGP hijack. In this blog, we’re going to talk about what the failure was, why it occurred, and what we’re doing to make sure this doesn’t happen again. Cloudflare introduced the 1.1.1.1 public DNS Resolver service in 2018. Since the announcement, 1.1.1.1 has become one of the most popular DNS Resolver IP addresses and it is free for anyone to use.Almost all of Cloudflare's services are made available to the Internet using a routing method known as anycast, a well-known technique intended to allow traffic for popular services to be served in many different locations across the Internet, increasing capacity and performance. This is the best way to ensure we can globally manage our traffic, but also means that problems with the advertisement of this address space can result in a global outage. Cloudflare announces these anycast routes to the Internet in order for traffic to those addresses to be delivered to a Cloudflare data center, providing services from many different places. Most Cloudflare services are provided globally, like the 1.1.1.1 public DNS Resolver, but a subset of services are specifically constrained to particular regions. These services are part of our Data Localization Suite (DLS), which allows customers ...