Analizar and understand DNS records
DNS records mapear domain names a IPs, mail servers, y otro datos. Aprender Un, AAAA, CNAME, MX, TXT, NS, y SOA record tipos.
- 1
DNS (Domain Name System) translates domain names to IP addresses. Record types: A (IPv4 address), AAAA (IPv6), CNAME (alias to another name), MX (mail server with priority), TXT (arbitrary text, used for SPF/DKIM/DMARC), NS (name server), SOA (start of authority), PTR (reverse lookup), SRV (service locator).
- 2 Información de direcciones IP →
Look up an IP address to understand its reverse DNS and network information. This complements DNS forward lookups — given an IP, find the hostname; given a hostname, find the IP.
- 3 Analizador de URL →
Analizar a domain name from a URL to extract the hostname for DNS lookup. The hostname is what DNS resolves — the URL may include port, path, and query that are not part of DNS.
Preguntas frecuentes
- What is the difference between A and CNAME?
- An A record maps a name directly to an IP address. A CNAME maps a name to another name (alias). Use A records for root domains (example.com) and direct mappings. Use CNAME for aliases (www.example.com → example.com). A name cannot have both A and CNAME records.
- What are TXT records used for?
- TXT records store arbitrary text, commonly used for: SPF (sender policy framework — which IPs can send email), DKIM (email signing key), DMARC (email policy), domain verification (Google, Microsoft), and MTA-STS. They are the Swiss Army knife of DNS.