It is important to do both A and AAAA DNS queries for all the domains Probes resolve during testing, as sometimes a “censor” will add the second stack (ex. IPv6) for a single-stack network endpoint to serve a blockpage.
- AS41843, ER-Telecom, Omsk, Russia makes “grani.ru” dual-stack with “5.3.3.17” and “2a02:2698:a002:1::3:17” while it’s “normally” single-stacked with 95.211.178.194