rdap-nagios

A nagios plugin to check domain name expiration date using an RDAP backend.

Documentation

This plugin discovers the authoritative RDAP endpoint for a domain through IANA's DNS RDAP bootstrap data, then reads the domain RDAP object and extracts its expiration event. For .ar domains, if RDAP transport, HTTP, JSON, or expiration-event lookup fails, it falls back to whois -h whois.nic.ar and parses NIC Argentina's expire: field.

It is intended to be a general RDAP expiration check. It was developed with a specific operational need for reliable .ar expiration monitoring, so .ar behavior should stay covered by tests when changing endpoint discovery or failure handling.

Installing

Install Python 3 dependencies:

pip3 install -r src/nagios_check_domain_expiration_rdap/requirements.txt

Copy the plugin to the Nagios host:

cp src/nagios_check_domain_expiration_rdap/nagios_check_domain_expiration_rdap.py /usr/local/bin/check_rdap_expire
chmod 755 /usr/local/bin/check_rdap_expire

If the target host uses a specific Python interpreter, keep the Nagios command pointed at that interpreter.

Testing

python3 src/nagios_check_domain_expiration_rdap/nagios_check_domain_expiration_rdap.py example.net
python3 -m unittest discover -s tests

Transport, HTTP, JSON, or missing-expiration failures return Nagios UNKNOWN with the endpoint in the error text. They are not treated as zero days to expiration. For .ar domains, the plugin first attempts the NIC Argentina WHOIS fallback before returning UNKNOWN.

Configure as Nagios Plugin

define command{
        command_name    check_rdap_expire
        command_line    /usr/local/bin/check_rdap_expire $ARG1$
}

Add a service check

define service{
 use                 generic-service
 host_name           localhost
 service_description EXPIRATION example.net
 check_command       check_rdap_expire!example.net
 check_interval      1440
 retry_interval      180
 max_check_attempts  3
}