Host record validation check

None.

Resource Records.

All nameserver IP addresses.

Every 5 minutes.

None.

High.

Purpose

The check validates that the Host record remains unaltered to its configured values/values.

A Host resource record can be of either type (A/AAAA/CNAME). If it is an A (IPv4 address record), and/or an AAAA (IPv6 address record), after validation the check will also look up its respective PTR records and report if they point back to the correct name.

We have opted to use the term Host instead of separating the types A, AAAA and CNAME into different check types. We figured this approach would be easiest and the most beneficial for our customers. Instead of having to configure A and AAAA records separately or need to figure out if a record is a CNAME or an address record, we simply grouped them together as a single Host record.

Event severities and messages

Records mach.
No detected changes to the Host record/records.

A/AAAA RRSIG validates correctly.*
DNSSEC signature validates.

{IP} incorrectly points to {Name}.
The PTR record points to a Name other than the Host.
Without a correct PTR record some authentication services may fail because they require a match between A/AAAA and PTR records.

{IP} has multiple pointer records.
Although not a direct violation of RFC 1035, it is still bad practice to use pointer record pointing to multiple host names.
With multiple PTR records, some authentication services may fail intermittently because they require a match between A/AAAA and PTR records.

A/AAAA query to name server {NS IP} resulted in NXDOMAIN.
Lists records that were received in the query response but does not exist in configuration database.

Unrecognised records.
Lists records that were received in the query response but does not exist in configuration database.

Missing records.
Lists records that should have been in the query response but weren’t.

A/AAAA RRSIG validation failure.*
DNSSEC signature for this resource record has failed validation.

* Require DNSSEC.