DNS Query

Function

Checks a given DNS record on a DNS server

Alarming

Transfer time, Execution time, Response code

This job must reside below a device which is itself a DNS server. It will not work on devices where no DNS service is running.

DNS Query detail

DNS Query parameters

Parameter

Description

Record type

Choose from one of the following record types:

  • A (forward) address record
    Used to map hostnames to an IP address.
    CNAMEs are also followed when checking A records.

  • AAAA (IPv6 forward) address record
    Used to map hostnames to an IPv6 address.

  • Cname canonical name record
    Alias of one name to another. The DNS lookup will continue by retrying the lookup with the new name

  • Ptr (reverse) pointer record
    A pointer to a canonical name. Unlike with CNAME, DNS processing does NOT proceed, only the name is returned. The most common use is implementing reverse DNS lookups by putting a PTR record for a hostname in the in-addr.arpa. domain that corresponds to an IP address.

  • Text
    Originally intended to carry arbitrary human-readable text in a DNS record. Since the early 1990s, however, this record is more often used to carry machine-readable data such as specified by RFC 1464, opportunistic encryption, Sender Policy Framework and Domain Keys.

  • Responsible person
    An RP-record specifies the mailbox of the person responsible for the host (domain name). A SOA-record defines the responsible person for an entire zone, but a zone may contain a large number of individual hosts and domain names for which different people are assigned responsibility. The RP-record makes it possible to identify the responsible person for individual domain names contained within the zone. To specify the "mailbox", replace the email address @ sign with a dot (.). Optionally specify the domain name for a TXT-record with additional information.

  • Service
    A generalized service location record, used for newer protocols instead of creating protocol-specific records such as MX.

Argument to check

Depends on the record type

Expected

Expected answer, depends on the record type. This parameter may contain wildcard characters such as * and ? when used with A and AAAA records.

DNS Query values and alarm limits

Value / Alarm limit

Description

Transfer time

Time to transfer the information

Execution time

Time to execute the query

Response code

0    No error
-1   General error

Error code

Generic job error code (see section Job error codes)

DNS Query examples

Example 1 - Ask for A record

Record type

A (forward)

Argument to check

skoor.com

Expected

195.49.42.34

Output 1

In case a wrong Expected entry was made or the IP address has changed in the DNS, a warning is returned:

Example 2 - Ask for the IP address mapped to an A record

Record type

PTR (reverse)

Argument to check

10.1.2.30

Expected

repo.junisphere.local

Output 2