Check DNS Serial

Project Notes

This check plugin allows you to check if all nameservers that host a DNS zone are up-to-date and deliver the same serial in the SOA-record of the zone.

The script is written in PHP and requires Net/DNS2.php (PHP Resolver library used to communicate with a DNS server). Install it with sudo apt-get install php-net-dns2 on Debian based systems.

Usage:
check-dns-serial.php <ip-of-primary-dns> <domain.tld>

Variables:
The following threshold variables can be set inside the script to control when Nagios should raise a WARNING or a CRITICAL:

# WARNING threshold if serials differ
$warn_threshold_delta = 5;
# CRITICAL threshold if serials differ
$crit_threshold_delta = 10;