Verify system lookups separately from direct DNS queries

When a new hostname resolves through direct DNS queries but ordinary HTTPS and browser navigation still report that it does not exist, test the operating system's host lookup separately. Resolver caches and the system lookup path can recover at different times. Do not infer browser readiness from direct DNS success or change valid hosting records to address a client lookup failure. Verify recovery with an ordinary HTTPS request and browser navigation; an IP-supplied request only verifies routing, TLS and content. Cache-reset effects depend on the operating system and are not a universal remedy.

Applies when: A newly configured hostname resolves at DNS servers but fails in local applications. Keywords: DNS negative cache hostname browser system resolver propagation lookup