Tutorials Articles

Everything you need for DNS lookups in PHP — from quick gethostbyname() calls to full dns_get_record() queries, checkdnsrr() validation, reverse DNS, and real-world email verification patterns.

Implement the DNS protocol in PHP — construct binary query packets with pack(), send raw UDP over sockets to port 53, and parse responses with unpack(). Pure PHP, no extensions required beyond sockets.

The critical difference between dns.lookup() and dns.resolve() that most Node.js tutorials miss — plus complete examples for every record type, custom resolvers, the Promises API, and TypeScript types.

Implement the DNS protocol in JavaScript — construct binary query packets with Buffer, send raw UDP to port 53 with dgram, and parse the responses. No dependencies, just Node.js built-ins.

Everything you need for DNS lookups in Python — from quick socket.getaddrinfo() calls to full-featured queries with dnspython. Covers all record types, custom nameservers, reverse DNS, async queries, and real-world patterns.

Learn the DNS protocol by implementing it — construct binary packets per RFC 1035, send raw UDP queries to port 53, and parse the responses. No libraries, just Python and sockets.

Master the dig command with real examples of every useful flag — from basic lookups and +short to +trace, +dnssec, batch queries, and scripting. The only dig reference you need.

Everything developers need to know about DNS queries — from recursive resolution to packet anatomy, query flags, and response codes. The foundation for building DNS tools or understanding existing ones.

Before you file an abuse report against that IP hammering your server, check the User-Agent. This guide covers how to identify web crawlers, manage them with robots.txt and server-level controls, and decide when to block, allow, or report.

A practical overview of every DNS diagnostic tool worth knowing — from dig and nslookup to packet captures and performance testing — with real examples of when and how to use each one.

Step-by-step guide to configuring custom domain email with Google Workspace and Microsoft 365. Learn how to set up MX records, SPF, DKIM, and DMARC for professional business email.

Learn how to diagnose and fix the most common DNS problems, from websites not loading to NXDOMAIN errors, using practical command-line tools and DNS Checker.

Switching hosting providers requires careful DNS verification to avoid downtime. Learn the step-by-step process for checking A, CNAME, MX, and NS records after a migration.

DNS propagation is the process of updating DNS records across servers worldwide. Learn how it works, why it takes up to 48 hours, and how to check propagation status in real time.