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Cloudflare

101 min read

DevOps•2026-01-14

What came first: the CNAME or the A record?

This post explains how a memory optimization change in Cloudflare's 1.1.1.1 DNS resolver accidentally reversed the order of CNAME records in DNS responses, causing widespread resolution failures on January 8, 2026.

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What came first: the CNAME or the A record?