Cloudflare DNS server down causes a large number of websites to go down

Cloudflare, a well-known network service provider in the United States, went down last night. This failure was mainly caused by the Cloudflare DNS domain name resolution server. The company mainly provides a content distribution network (CDN) and DDoS protection services for website operators.

A large number of websites use the domain name resolution server provided by this company, and the failure of the domain name resolution server will directly cause the website to be no longer accessible.

“Cloudflare Schriftzug und Wolken-Logo, vergrößert dargestellt unter einer Lupe”by verchmarco is licensed under CC BY 2.0

Due to the failure of the DNS server, users may not find the IP address when they try to access some websites. This is the result after the DNS server fails.

When a large number of websites cannot be opened normally, many users and website operators worry that Cloudflare is down due to a large-scale network attack.

However, the company issued a log saying that there was a system anomaly, was not a network attack, but that a route in the server system was faulty and the resolution failed.

After the fault lasted for about 1 hour, the company repaired the anomaly. The websites that could not find the IP address before began to resume analysis one after another and the website access returned to normal.

The company did not disclose how many specific sites were affected, but in terms of its size, the number of affected sites may exceed hundreds of thousands or even higher.

Of course, the probability of such a failure is very low, which is a very unexpected problem, and the website operator does not need to replace other servers because of this failure.