{"kind":"host","input":"readthedocs.io","report":{"host":"readthedocs.io","checkedAt":"2026-10-31T22:05:01.729Z","a":{"status":"found","values":["104.16.253.120","104.16.254.120"],"ttl":13,"via":"Cloudflare","cname":[]},"aaaa":{"status":"found","values":["2606:4700::6810:fd78","2606:4700::6810:fe78"],"ttl":300,"via":"Cloudflare","cname":[]},"verdict":"dual-stack","www":{"host":"www.readthedocs.io","a":{"status":"found","values":["104.16.254.120","104.16.253.120"],"ttl":300,"via":"Cloudflare","cname":[]},"aaaa":{"status":"found","values":["2606:4700::6810:fd78","2606:4700::6810:fe78"],"ttl":300,"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":"readthedocs.io has 2 IPv6 addresses and answers on every one we tested.","addresses":[{"address":"2606:4700::6810:fd78","result":"answers","port":443},{"address":"2606:4700::6810:fe78","result":"answers","port":443}]},{"key":"www","label":"www over IPv6","status":"pass","detail":"www.readthedocs.io has 2 IPv6 addresses and answers on every one we tested.","addresses":[{"address":"2606:4700::6810:fd78","result":"answers","port":443},{"address":"2606:4700::6810:fe78","result":"answers","port":443}]},{"key":"mail","label":"Mail servers (MX) have IPv6","status":"pass","detail":"Every mail server has an AAAA record.","hosts":[{"host":"aspmx.l.google.com","ipv6":true},{"host":"aspmx2.googlemail.com","ipv6":true},{"host":"aspmx3.googlemail.com","ipv6":true},{"host":"alt1.aspmx.l.google.com","ipv6":true},{"host":"alt2.aspmx.l.google.com","ipv6":true}]},{"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":"ivan.ns.cloudflare.com","ipv6":true},{"host":"tegan.ns.cloudflare.com","ipv6":true}]}]},"https":{"status":"pass","summary":"Loads over IPv6 with a valid certificate after 3 redirects: HTTP 200.","hops":[{"url":"https://readthedocs.io/","address":"2606:4700::6810:fd78","status":302,"tls":"valid"},{"url":"https://readthedocs.org/","address":"2606:4700::6812:71d","status":302,"tls":"valid"},{"url":"https://app.readthedocs.org/welcome/","address":"2606:4700::6812:71d","status":302,"tls":"valid"},{"url":"https://about.readthedocs.com/?ref=app.readthedocs.org","address":"2606:4700::6810:fd78","status":200,"tls":"valid"}]},"receiptId":"AFsrtukFKU","reused":true,"measuredAt":"2026-10-31T22:05:01.892Z"}