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If you are new to DNS, please read this note on
terminology. Thanks.
RECORD TYPES
This tool models the route a typical DNS client takes to fetch an answer
to a question. The question always consists of a domain name and a record
type. There can be many different records for each domain name, for
example amongst the simplest are A records to indicate that there is a
corresponding IP address for the name and MX records to indicate
that there is a mail host for this name. These records can co-exist with
each other. Other records are more complicated,
for example a CNAME cannot be present with any other record, as it
says that all information for the domain name can be found elsewhere - at
the canonical name.
The record types are all documented in the DNS RFC documents
(1034,
1035),
but here is a summary that might help you.
If you don't understand any of this, enter www.example.com and
select A as the record type.
| Type |
Description |
Example |
Notes |
| A |
A host address |
www.example.com |
This looks up the equivalent IP address(es) of the name
you entered |
| SOA |
Identifies the start of a zone of authority |
example.com |
Zone boundary, typically a "domain name" in the commercial
sense |
| CNAME |
Identifies the canonical name of an alias. |
mail.example.com |
This looks up the real name of this entry * |
| MX |
Identifies a mail exchange for the domain |
example.com |
This looks up the mail servers for this domain name ** |
| NS |
The authoritative name server for the domain |
example.com |
This looks up the name servers for this domain name |
| PTR |
A domain name pointer |
4.3.2.1.in-addr.arpa |
This looks up the name for a given IP address.
For 1.2.3.4 enter 4.3.2.1.in-addr.arpa |
| ANY |
Any records for the domain |
example.com |
Asks the name server to respond with everything *** |
* dnscheck will indirect through CNAMEs automatically for other
record types (there is an option to turn this off).
** mail clients will attempt direct delivery via an A record if there is no
MX record for a domain name
(RFC2821 section 5).
*** ANY queries on zone boundaries will be answered by the parent name
server: dnscheck will not be referred to the delegated nameserver
(which is why you see NS records and not an SOA record).
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