Reported interview periodMay 2026
Implement a DNS Resolver with Aliases and TTL
Build an in-memory resolver over A and CNAME records.
Practice focusRequirements - Normalize domain names case-insensitively and ignore a trailing dot. - An A record resolves directly to its address while live. - A CNAME follows its target recursively until a live A record is found. - Each record has type ( A or CNAME ) and value (address or target). Optional ttl is a duration; set at defaults to zero. A missing or null ttl means no expiration. - A record expires when now = set at + ttl . - Any expired or missing link makes resolution fail.…