DNSCanary

DNSCanary is a web app (with optional lightweight agent) that continuously tests your DNS from multiple regions and resolvers to detect outages, propagation issues, and misconfigurations before they impact customers. You define “canary checks” for critical records (A/AAAA/CNAME/MX/TXT/CAA), expected answers, TTL ranges, and DNSSEC status. The system runs synthetic queries against public resolvers (Cloudflare, Google, Quad9) and authoritative nameservers, compares results, and alerts on drift, SERVFAIL spikes, NXDOMAIN anomalies, or unexpected record changes. It also tracks registrar/NS changes and provides a timeline view that correlates changes with incidents. This is not a full DNS host; it’s an independent verification layer that works with any provider. The product lives or dies on reliability and clear, actionable alerts—not pretty dashboards.