Cloudflares 1.1.1 DNS service was disrupted by an imaginary DDoS attack on its infrastructure on 31 May. The company has now admitted it suffered an unusual and rare type of attack an imaginary one. The DNS resolver suddenly disappeared for a 17-minute disruption to DNS resolution for all network devices, starting at 17:58 UTC. The service was inadvertently blocked by home gateways supplied by AT&T, the company says. The incident is not the first incident to affect the service since it launched on 1 April.”]
Source: https://nakedsecurity.sophos.com/2018/06/04/cloudflare-mistakes-own-1-1-1-1-dns-for-ddos-attack/