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Earlier today, Cloudflare terminated the account of the Daily Stormer. We've stopped proxying their traffic and stopped answering DNS requests for their sites. We've taken measures to ensure that they cannot sign up for Cloudflare's services ever again.
Cloudflare's mission is to help build a better Internet. We're excited today to take another step toward that mission with the launch of 1.1.1.1 — the Internet's fastest, privacy-first consumer DNS service. This post will talk a little about what that is and a lot about why we decided to do it.
Today at 1651 UTC, we opened an internal incident entitled "Facebook DNS lookup returning SERVFAIL" because we were worried that something was wrong with our DNS resolver 1.1.1.1. But as we were about to post on our public status page we realized something else more serious was going on.
Today at 10:30UTC, the Internet had a small heart attack. A small company in Northern Pennsylvania became a preferred path of many Internet routes through Verizon (AS701), a major Internet transit provider.
On July 14th, 2025, Cloudflare made a change to our service topologies that caused an outage for 1.1.1.1 on the edge, resulting in downtime for 62 minutes for customers using the 1.1.1.1 public DNS Resolver as well as intermittent degradation of service for Gateway DNS. We’re deeply sorry for this outage. This outage was the result of an internal configuration error and not the result of an attack or a BGP hijack. In this blog post, we’re going to talk about what the failure was, why it…
Oblivious DoH (ODoH) makes secure DNS over HTTPS (DoH) queries into private queries which prevent the leakage of client IP addresses to resolvers. The new proposed ODoH standard addresses this problem and today we are enabling users to use this protocol with 1.1.1.1
Almost nine years ago, Cloudflare was a tiny company and I was a customer not an employee. Cloudflare had launched a month earlier and one day alerting told me that my little site, jgc.org, didn’t seem to have working DNS any more.
There has been speculation about the cause of a BGP anomaly observed in Venezuela on January 2. We take a look at BGP route leaks, and dive into what the data suggests caused the anomaly in question.
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.
Explore HTTP/3 from root to tip and discover the backstory of this new HTTP syntax that works on top of the IETF QUIC transport.
This morning at 09:47 UTC CloudFlare effectively dropped off the Internet. The outage affected all of CloudFlare's services including DNS and any services that rely on our web proxy.
We are now happy to announce that QUIC and HTTP/3 support is available on the Cloudflare edge network. We’re excited to be joined in this announcement by Google Chrome and Mozilla Firefox, two of the leading browser vendors and partners in our effort to make the web faster and more reliable for all.
Cloudflare suffered a service outage on February 20, 2026. A subset of customers who use Cloudflare’s Bring Your Own IP (BYOIP) service saw their routes to the Internet withdrawn via Border Gateway Protocol (BGP).
As was mentioned in the original 1.1.1.1 blog post, our policy is to never write client IP addresses to disk and wipe all logs within 24 hours. Still some folks might not want to reveal their IP address to the resolver at all. This is why we are launching a Tor hidden service for our resolver.
Today CloudFlare is introducing HTTP/2 support for all customers using SSL/TLS connections, while still supporting SPDY. There is no need to make a decision between SPDY or HTTP/2.
We announced support for HTTP/3, the successor to HTTP/2, during Cloudflare’s birthday week last year. Our goal is and has always been to help build a better Internet. Even though HTTP/3 is still in draft status, we've seen a lot of interest from our users.
On 4 October 2023, Cloudflare experienced DNS resolution problems. Some users may have received SERVFAIL DNS responses to valid queries. 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
Over the few last hours, a dozen news stories have broken about how an attacker attempted (and perhaps managed) to steal cryptocurrencies using a BGP leak.
In two previous posts we've discussed how to receive 1M UDP packets per second and how to reduce the round trip time. We did the experiments on Linux and the performance was very good considering it's a general purpose operating system.
The “HTTP/2 Rapid Reset” attack exploits a weakness in the HTTP/2 protocol to generate enormous, hyper-volumetric DDoS attacks. Cloudflare has mitigated a barrage of these attacks in recent months, including an attack three times larger than any previous attack we’ve observed
Cloudflare's customers can now take advantage of Zstandard (zstd) compression, offering 42% faster compression than Brotli and 11.3% more efficiency than GZIP. We're further optimizing performance for our customers with HTTP/3 prioritization and BBR congestion control, and enhancing privacy through Encrypted Client Hello (ECH).
Ladies and gentlemen, I would like you to welcome the new shiny RFC8482, which effectively deprecates DNS ANY query type. DNS ANY was a "meta-query" - think about it as a similar thing to the common A, AAAA, MX or SRV query types, but unlike these it wasn't a real query type - it was special.
Advancing the state of the art of HTTP/2 to deliver a faster user experience. See why it matters and how much of a differenc
Scaling up TCP servers is usually straightforward. Most deployments start by using a single process setup. When the need arises more worker processes are added.