2026-01-19 Hacker News Top Articles and Its Summaries
1. What came first: the CNAME or the A record? Total comment counts : 22 Summary An update to 1.1.1.1 to reduce memory usage inadvertently changed the order of DNS records, placing CNAMEs at the bottom of answers instead of upfront. Some resolvers rely on CNAMEs appearing first to follow alias chains, causing resolution failures when expected names don’t match. A memory-optimization change merged CNAMEs into the existing answer list rather than building a fresh chain, triggering failures in glibc getaddrinfo and Cisco DNSC; most clients (e....