If you have only configured your DNS using A-type records, you might be surprised to see a large number of AAAA queries in your DNS logs. This happens due to the global shortage of IPv4 addresses that is causing a large-scale migration of services onto IPv6 networks that solve the issue of IPv4 capacity running out.
While the vast majority of global infrastructure is currently still running on IPv4 or a double stack of IPv4 and IPv6, there is an ongoing effort to resolve the capacity issues by migrating traffic to IPv6-enabled networks.
Due to this, various clients, browsers, and programs that run on IPv6-enabled networks began prioritizing IPv6 queries as default. When a browser attempts to resolve a domain name, it will first issue an AAAA query to attempt to acquire an IPv6 address. If the AAAA record with an IPv6 address is not configured for the queried domain, the client will then attempt to issue an A-type query to resolve the domain with an IPv4 address.
When this happens, Bunny DNS will still log the original AAAA queries with the empty answer. These queries are harmless, however, we would encourage configuring both A and AAAA records to improve the resolution time for your domain names and effectively to also improve the performance of your website or application.