Cache snooping is impossible on stub-zones
When a caching BIND server is configured with a static stub zone it's not possible to query the cache with a -RD
query for any entries at or below that zone cut - the server always returns REFUSED
.
Tested with BIND 9.13.3 (Development Release) <id:215e3fde22>
.
Since we otherwise do permit cache snooping this should probably be considered a bug.