Oracle Cloud default DNS resolver causes incorrect GeoDNS responses, because it doesn't seem to supp
SummaryOracle Cloud default DNS resolver needs to be fixed and support EDNS properly, to fix incorrect GeoDNS query responses.
GeoDNS is very commonly used, especially for CDNs.
However, my tests show queries to the default Oracle Cloud DNS resolver result in domain IPs being resolved to USA in other non-USA regions(for CDN services using GeoDNS and AWS Route 53 Geo DNS results) .
EDNS(https://en.wikipedia.org/wiki/EDNS_Client_Subnet) is required for proper Geo DNS resolution.
Either the default Oracle Cloud DNS resolver is not sending EDNS or it is sending the wrong subnet for EDNS.