{"kind":"host","input":"mx.web4u.cz","report":{"host":"mx.web4u.cz","checkedAt":"2026-11-15T15:54:37.692Z","a":{"status":"found","values":["81.91.87.12"],"ttl":60,"via":"Cloudflare","cname":[]},"aaaa":{"status":"found","values":["2001:1568::7012"],"ttl":60,"via":"Cloudflare","cname":[]},"verdict":"dual-stack"},"readiness":{"grade":"A","summary":"Website, mail and DNS all work over IPv6.","reachabilityTested":true,"checks":[{"key":"web","label":"Website over IPv6","status":"pass","detail":"mx.web4u.cz has an AAAA record and answers on it.","addresses":[{"address":"2001:1568::7012","result":"answers","port":80}]},{"key":"mail","label":"Mail servers (MX) have IPv6","status":"pass","detail":"No MX records, so mail goes to the domain's own address (implicit MX). It has an AAAA record."},{"key":"dns","label":"Nameservers have IPv6","status":"pass","detail":"2 of 2 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up.","hosts":[{"host":"ns.web4u.cz","ipv6":true},{"host":"ns2.web4u.cz","ipv6":true}]}]},"https":{"status":"unknown","summary":"mx.web4u.cz didn't complete an HTTPS request over IPv6 (timed out).","hops":[{"url":"https://mx.web4u.cz/","address":"2001:1568::7012","note":"timed out"}]},"receiptId":"FHefG6UsNY","reused":true,"measuredAt":"2026-11-15T15:54:45.787Z"}