How DNS Resolution, nslookup, and WHOIS/RDAP Work Together

Every web request begins long before a browser renders HTML or establishes an HTTPS connection. First, the domain registry (verified via WHOIS / RDAP) delegates authority to your Nameservers (NS). Second, recursive DNS resolvers (checked via nslookup) query those authoritative nameservers for A/AAAA IP addresses, MX mail routes, and TXT security policies.

Zero-Downtime Custom Domain Cutover & CLI Verification

To cut over a production domain without dropping live visitor traffic or business emails, verify both registry status and record propagation in sequence.

Domain & Network Diagnostics Playbook: Mastering DNS Records, nslookup, WHOIS/RDAP, and SSL Handshakes | 找到你需要的帮助。 — Fantatree — Before migrating a website or custom domain, lowering DNS TTL to 300 seconds 24 hours in advance eliminates stale resolver cache blackouts. nslookup and authoritative record checks (A, AAAA, CNAME, MX, NS, TXT, CAA, SOA) isolate whether an outage is caused by DNS propagation, TLS certificates, or origin routing. IANA RDAP (Registration Data Access Protocol) provides structured, JSON-based domain ownership, registrar lock (EPP clientTransferProhibited), and DNSSEC verification over HTTPS.