{"kind":"host","input":"columbia.edu","report":{"host":"columbia.edu","checkedAt":"2026-11-02T16:56:37.043Z","a":{"status":"found","values":["162.159.128.65","162.159.138.64"],"ttl":2692,"via":"Cloudflare","cname":[]},"aaaa":{"status":"absent","via":"Cloudflare","cname":[]},"verdict":"ipv4-only","www":{"host":"www.columbia.edu","a":{"status":"found","values":["162.159.138.64","162.159.128.65"],"ttl":189,"via":"Cloudflare","cname":[]},"aaaa":{"status":"absent","via":"Cloudflare","cname":[]},"verdict":"ipv4-only"}},"readiness":{"grade":"D","summary":"The website has no IPv6.","reachabilityTested":true,"checks":[{"key":"web","label":"Website over IPv6","status":"fail","detail":"columbia.edu has no AAAA record."},{"key":"www","label":"www over IPv6","status":"fail","detail":"www.columbia.edu has no AAAA record."},{"key":"mail","label":"Mail servers (MX) have IPv6","status":"fail","detail":"None of the mail servers has an AAAA record.","hosts":[{"host":"mxb-00364e01.gslb.pphosted.com","ipv6":false},{"host":"mxa-00364e01.gslb.pphosted.com","ipv6":false}]},{"key":"dns","label":"Nameservers have IPv6","status":"pass","detail":"2 of 4 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up.","hosts":[{"host":"ns1.lse.ac.uk","ipv6":false},{"host":"auth2.dns.cogentco.com","ipv6":true},{"host":"auth1.dns.cogentco.com","ipv6":true},{"host":"ext-ns1.columbia.edu","ipv6":false}]}]},"receiptId":"zsdmQFJhej","reused":true,"measuredAt":"2026-11-02T16:56:37.230Z"}