MX resolution check
Prerequisites:
MX RR’s configured.
Package:
Mail.
Executed on:
Validating resolver.
Check interval:
Every 5 minutes.
Impact on Availability:
None.
Impact on Integrity:
None.
Purpose
The check verify that all MX record resolves to at least one IP address.
The exchanger field in the MX resource record points to the owner name of the host responsible for receiving email. This host name must be resolvable for the MX record to work properly and for mail to be delivered.
Event severities and messages
INFO
All MX records resolve to IPv4 and IPv6 addresses.
WARNING
{MX hostname} does not resolve to an IPv6 address.
Your mail domain can’t receive emails from MTA sources with IPv6 only implemented. This WARNING message does not affect the overall Availability metric but is here to remind about the ongoing deployment of IPv6 as the successor of IP version 4.
ERROR
Your mail domain can’t receive emails from MTA sources with IPv6 only implemented. This WARNING message does not affect the overall Availability metric but is here to remind about the ongoing deployment of IPv6 as the successor of IP version 4.
Solutions, tips & tricks
As all organisations rely on email, it is important to be as connected as possible. The number of IPv6-only MTAs is growing every day. If you are not receiving email over IPv6, it is a good idea to start planning for it.