DNS & EMAIL
DNS Lookup
Query A, AAAA, MX, TXT, NS, CNAME, SOA, CAA, SRV and PTR records from the server resolver.
39DExternal testRuns from the toolbox server
RUN TEST
DNS Lookup
HOW IT WORKS
About the DNS Lookup
DNS translates names into addresses and publishes service, mail and policy information. This checker asks the resolver configured on the toolbox server and returns the records in structured form.
How to use this result
- Run the test from this server.Use a public hostname, address, prefix or ASN in the format requested above.
- Compare with another observation point.Run a local command or use a second provider to identify location-specific behaviour.
- Correlate related evidence.Use the related tools below to compare DNS, routes, ports, TLS and application responses.
- Keep the time and context.Routing, DNS caches and reputation data change, so record when the result was collected.
Common interpretation issues
- Cached answers can remain visible until their TTL expires.
- CNAME records are not normally placed at a DNS zone apex.
- TXT values may be split into several quoted strings by DNS software.
NEED HELP INTERPRETING THE RESULT?
39D supports business networks, cyber security and managed IT.
For ongoing support or a larger infrastructure project, speak to the 39D team.
Frequently asked questions
Which record should I use for email?
MX identifies receiving mail servers; SPF and DMARC are normally published as TXT records.
Why is a new record missing?
The old answer may still be cached, or the authoritative nameservers may not all have the same zone data.