DNS Wiki & Resource Hub

Plain-English guides to DNS records, security protocols, and troubleshooting workflows.

Explore our comprehensive documentation on common DNS record types, typical misconfigurations, and how to validate each record online. Use the linked tools within the guides to verify live DNS answers and compare resolver results.

Core DNS Records

A record

IPv4 address mapping, apex vs www, and common pointing mistakes.

AAAA record

IPv6 addressing, dual stack setup, and connectivity pitfalls.

CNAME record

Aliases, SaaS integrations, and the apex domain rule.

NS record

Delegation, authoritative name servers, and registrar alignment.

SOA record

Zone metadata, primary nameservers, serials, and refresh timers.

Email & Authentication

MX record

Mail routing priorities, MX target requirements, and delivery checks.

TXT record

Verification strings, character limits, and machine-readable data.

SPF

Sender policy, 10 DNS lookup limits, and soft vs. hard fails.

DMARC

Policy enforcement, SPF/DKIM alignment, and XML reporting.

Advanced & Telecom Routing

PTR record

Reverse DNS (rDNS), in-addr.arpa, and IP ownership constraints.

NAPTR record

VoIP, SIP routing, ENUM, and regular expression (regex) rules.

SRV record

Service discovery, priority vs. weight, port formatting, and strict target rules.

Security & Encryption

DNSSEC

Cryptographic signatures, the Chain of Trust, and SERVFAIL errors.

CAA record

Restricting Certificate Authorities, Let's Encrypt, and issue tags.

TLSA record

DANE protocol, certificate pinning, and securing SMTP connections.

DNS Concepts & Workflows

DNS Propagation

How DNS caching works, TTL (Time to Live), and why updates take 48 hours.

Email DNS Security

How MX, SPF, DKIM, and DMARC work together to guarantee inbox delivery.

SSL/PKI DNS

The ultimate zero-trust setup using CAA, TLSA, and DNSSEC combined.