{"kind":"host","input":"mx.colorado.edu","report":{"host":"mx.colorado.edu","checkedAt":"2026-11-03T03:05:07.248Z","a":{"status":"found","values":["52.101.11.17","40.93.192.4","52.101.8.32","52.101.9.34"],"ttl":10,"via":"Cloudflare","cname":["colorado-edu.mail.protection.outlook.com"]},"aaaa":{"status":"found","values":["2a01:111:f403:f909::4","2a01:111:f403:f913::2","2a01:111:f403:f90d::1","2a01:111:f403:c95d::"],"ttl":10,"via":"Cloudflare","cname":["colorado-edu.mail.protection.outlook.com"]},"verdict":"dual-stack"},"readiness":{"grade":"F","summary":"Publishes IPv6 but doesn't answer on it — worse than having none.","reachabilityTested":true,"checks":[{"key":"web","label":"Website over IPv6","status":"broken","detail":"mx.colorado.edu has an AAAA record, but nothing answered on ports 443 or 80. IPv6 visitors wait for a timeout before falling back to IPv4.","addresses":[{"address":"2a01:111:f403:f909::4","result":"no answer"},{"address":"2a01:111:f403:f913::2","result":"no answer"},{"address":"2a01:111:f403:f90d::1","result":"no answer"},{"address":"2a01:111:f403:c95d::","result":"no answer"}]},{"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":"6 of 6 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up.","hosts":[{"host":"a11-66.akam.net","ipv6":true},{"host":"a1-153.akam.net","ipv6":true},{"host":"a3-66.akam.net","ipv6":true},{"host":"a2-67.akam.net","ipv6":true},{"host":"a22-67.akam.net","ipv6":true},{"host":"a20-65.akam.net","ipv6":true}]}]},"receiptId":"r37DnfQzwe","reused":true,"measuredAt":"2026-11-03T03:05:13.255Z"}