Lookup · RFC 1035
DNS lookup
Ask DNS for any name and any record type. The answer comes from our resolver, with the TTL left, the aliases followed and whether it was validated with DNSSEC.
How to read a DNS answer
- NXDOMAIN, NODATA or an error
NXDOMAIN: the name does not exist. NODATA: the name exists but lacks the type asked (RFC 2308 §2.1, §2.2). Both are definite answers. A timeout or SERVFAIL says nothing about the record, so we show them as "unavailable".
- TTL
How long the answer may be cached, in seconds; the number shown is what is left in our resolver's cache. Negative answers are cached too, at most for the SOA MINIMUM field (RFC 2308 §4, §5): a newly created record may only appear after it.
- DNSSEC
"DNSSEC validated" means our resolver checked the signatures and considers the answer authentic (the AD bit, RFC 4035 §3.2.3). "No DNSSEC": the zone is not signed, or the chain of trust does not reach it.
- Aliases (CNAME)
A CNAME points a name at another, and the resolver follows the chain and answers for its target (RFC 1034 §3.6.2). A name with a CNAME can have no other records, and MX and NS must not point at an alias (RFC 2181 §10.3).
AIPv4 addressAAAAIPv6 addressMXMail serversTXTText: SPF, DMARC, DKIM…CNAMEAliasNSDNS serversSOAZone dataPTRReverse DNSCAACertificate issuersSRVServices
Sources: RFC 1034 · RFC 1035 · RFC 2181 · RFC 2308 · RFC 4035