Stub resolver
A stub resolver is the lightweight DNS client built into an operating system or application that forwards every lookup straight to a recursive resolver, rather than walking the DNS hierarchy itself. RFC 1123 explicitly names this pattern, describing most end-host resolvers as minimal stub resolvers that depend on a nearby recursive resolver to do the iterative lookups RFC 1034 defines. Most operating systems ship a stub resolver pointed at whatever resolver address DHCP, a router, or an ISP supplies, though it can be repointed at a different one, including a Protective DNS or DNS-over-HTTPS resolver, to change what queries see and get filtered. A stub resolver does no caching or validation on its own, so behavior like DNSSEC validation or content filtering depends entirely on the recursive resolver it's configured to use. AdminKit's DNS resolver test tool checks which resolver a device is actually using and how it answers.
By AdminKit team, Netbase JSC · Updated