How to Diagnose a Website That Becomes Unavailable After a DNS Cache Expires

A service may seem healthy while cached DNS answers point clients to an old or unreachable address. The issue becomes visible as caches refresh at different times.

What to check

Compare authoritative and recursive answers, TTLs, server health, proxy configuration, and old address availability. Review recent record and migration changes.

Recommended next step

Keep the old endpoint available during transition where possible and validate DNS from multiple resolvers. Informatix Systems can investigate hosting and DNS behavior.