Overview
Enterprise Nodes use the network resolver for all test types except DNS. This is similar to what Last-Mile nodes and real users experience on ISPs. DNS test types will mimic a resolver that always queries the TLDs (Top Level Domains) first. This is how the resolver for all test types work, excluding DNS on Catchpoint Backbone nodes. This can cause issues where tests get different DNS results than what is experienced with DNS test types (specifically experience and traversal).
DNS Resolver
A resolver on a network might have a different set of rules and cache than those mimicked Catchpoint DNS test types. This could result in Web Tests resolving domains without issue while the DNS test fails. This is due to the fact the network resolver might have a predefined cache or rules for resolving that domain. The DNS test does not have knowledge of this and tries to query the TLDs which have no knowledge of the domain and fail. This is similar to how Last Mile nodes (or resolvers used by real users) never give a failure for a bad domain but send you to a search page.
DNS Troubleshooting
When attempting to troubleshoot DNS issues and failures on Enterprise nodes where this discrepancy is apparent, it is recommended clients do direct DNS tests to the network resolver. The direct test will show what answer the network's resolver is producing for use by Catchpoint web tests.