How we saved 100 terabytes of memory by optimizing 1.1.1.1’s DNS cache
Five Rust-level memory optimizations to the DNS cache layout of Big Pineapple cut per-entry memory by 56%, freeing approximately 100 TB of memory across Cloudflare's fleet.
Sebastiaan Neuteboom
Systems Engineer
A broken DNSSEC rollover took down .al. Now 1.1.1.1 tells you when validation is bypassed
When a failed DNSSEC key rollover took down the .al TLD, we deployed a Negative Trust Anchor to restore resolution. This time, though, clients didn't have to take our word for it: 1.1.1.1 returned EDE 33, a new DNS error code that signals directly in the response that DNSSEC validation was bypassed.
When DNSSEC goes wrong: how we responded to the .de TLD outage
On May 5, 2026, DENIC published broken DNSSEC signatures for the .de TLD, making millions of domains unreachable. Here's what 1.1.1.1 saw, how serve stale cushioned the impact, and how we restored resolution.
What came first: the CNAME or the A record?
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.
