Bài học theo mô-đun (3/4)
Client, resolver e autorità
Clients, resolvers, and authorities
DNS work is shared among different actors. A stub resolver on a device asks a recursive resolver for an answer. The recursive resolver checks its cache and, when needed, follows referrals. An authoritative server publishes data for a zone and answers from that source.
Worked example
When a laptop opens shop.example.test, its stub usually sends a request to the configured recursive resolver. The resolver may already have the record cached. If not, it contacts the relevant authorities and returns the result to the laptop.
The application, stub, recursive resolver, and authoritative servers are separate roles, even when one device or provider operates more than one of them. Knowing which actor produced a response makes troubleshooting easier.
Check your understanding
Choose the best answer. This quiz runs locally and sends no DNS queries to real domains.
Which component normally follows referrals on behalf of a client?