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How does the Node.js 'dns' module differ from browser-based DNS resolution?

Q: How does the Node.js 'dns' module differ from browser-based DNS resolution?

**TL;DR.** Node's dns module gives you **programmatic** DNS with two flavors: dns.lookup (uses the OS resolver via the **libuv thread pool**, honoring /etc/hosts ) and dns.resolve* (talks to DNS servers directly over the **network**, no thread pool). Browsers, by contrast, resolve DNS **internally** with their own cache and give pages no DNS API. dns.lookup OS resolver honors /etc/hosts uses thread pool ⚠ <rect class='d-box-muted' x='240' y='30' width='200' heig

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Tests deep understanding of Node's networking capabilities and how it resolves domain names.

dnsnetworkingmodules

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lookup vs resolve

import dns from 'node:dns/promises';

// OS resolver (thread pool, honors hosts file):
console.log(await dns.lookup('example.com'));        // { address, family }

// Direct DNS query, specific record types (no thread pool):
console.log(await dns.resolveMx('example.com'));     // mail servers
console.log(await dns.resolve4('example.com'));      // A records

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