Learn how DNS works: hierarchy, records (A, CNAME, MX, TXT), TTL caching, and the full resolution process. Plus commands to view and clear DNS cache.

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DNS translates domain names to IP addresses through a hierarchical system of root servers, TLD servers, and authoritative nameservers. The resolution process involves multiple caching layers (browser, OS, router, ISP resolver) that store results based on TTL values. Key DNS record types include A (IPv4), AAAA (IPv6), CNAME (aliases), MX (email routing), and TXT (verification). Understanding TTL is crucial for managing DNS propagation during server migrations. DNS also enables advanced patterns like load balancing, failover, and geographic routing for distributed systems.

DNS Explained - How Domain Names Get Resolved