Knowledge base

A record

Learn what a DNS A record is, how it maps domains to IPv4 addresses, common uses, lookup methods, and troubleshooting tips.

AAAA record

Learn what a DNS AAAA record is, how it maps domains to IPv6 addresses, dual-stack setup, lookup methods, and troubleshooting tips.

CNAME record

Learn what a DNS CNAME record is, how it creates domain aliases, key limitations (especially for root domains), lookup methods, best practices, and troubleshooting.

MX record

Learn what a DNS MX record is, how it directs email to the correct mail servers using priorities, common setups (Google Workspace, Microsoft 365, custom), lookup methods, and troubleshooting tips.

NS record

Learn what a DNS NS record is, how it delegates authority to name servers, why multiple are essential for redundancy, lookup methods, common setups (Cloudflare, Route 53, custom), and troubleshooting.

PTR record

Learn what a DNS PTR record is, how it enables reverse lookups (IP to domain name), why it's critical for email deliverability, who manages it, lookup methods, and best practices for forward-confirmed reverse DNS (FCrDNS).

SOA record

Learn what a DNS SOA record is, why every zone requires exactly one, its key components (primary NS, admin email, serial, timers), how it controls zone transfers and caching, lookup methods, and best practices.

TXT record

Learn what a DNS TXT record is, its versatile uses for email authentication (SPF, DKIM, DMARC), domain verification, common formats, lookup methods, and best practices to avoid common pitfalls.

CAA record

Learn what a DNS CAA record is, how it controls which Certificate Authorities can issue SSL/TLS certificates for your domain, examples, lookup methods, and best practices.

DNS TTL

Learn what DNS TTL is, how it controls caching and propagation speed, recommended values for different use cases, how to manage TTL before changes, and common mistakes to avoid.

WHOIS fields

Learn how to read WHOIS and RDAP output for domains, IP addresses, and ASNs. Understand every field — registrar, expiry, status codes, RIR allocation, abuse contacts, and why some data is redacted.

SPF record

Learn what an SPF record is, how it prevents email spoofing by authorizing sending mail servers, how to read and write SPF syntax, common setups for Google and Microsoft 365, and how to troubleshoot failures.

DKIM record

Learn what a DKIM record is, how it uses cryptographic signatures to prove email authenticity, how to find and verify DKIM selectors, common setup for Google Workspace and Microsoft 365, and why DKIM is essential for email deliverability.

DMARC record

Learn what a DMARC record is, how it ties together SPF and DKIM to block email spoofing, how to read DMARC policy tags, how to safely roll out p=reject, and how to use aggregate reports to monitor your email authentication.

DNS providers

Resolver names accepted by DNS tools and the public API, with defaults and when to use each option.