What are common DNS record types (A, AAAA, CNAME, MX, TXT, SRV)?

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DNS is the first hop in almost every request — resolution modes, caching, routing policies, and security are core interview topics. What are common DNS record types (A, AAAA, CNAME, MX, TXT, SRV)? — define the concept, explain how it works in production, and call out trade-offs a…