check_rlm.py — Nagios Plugin for Reprise License Manager

Looking for FlexLM/FlexNet monitoring? See nagios-check-flexlm — same output format, same check modes, built for FlexLM servers.

A Nagios/Nagios XI plugin for monitoring Reprise License Manager (RLM) license servers. The plugin is a single self-contained Python 3.9+ script with zero external dependencies that invokes rlmutil rlmstat to check license server health, license expiry, and license usage.

It returns standard Nagios exit codes and performance data suitable for graphing with PNP4Nagios or Grafana, and also supports JSON output mode and structured file logging.

Requirements

• Python 3.9+ — Uses modern type hints and standard library features
• rlmutil v18.0 — The RLM command-line utility must be accessible on the Nagios server (either in $PATH or specified via --rlmutil-path). Tested with rlmutil v18.0.

Installation

1. Copy the plugin to your Nagios plugins directory:

   scp check_rlm.py nagios-server:/usr/local/nagios/libexec/

2. Set the executable permission:

   chmod +x /usr/local/nagios/libexec/check_rlm.py

3. Verify Python version (3.9+ required):

   python3 --version

4. Confirm the plugin runs:

   /usr/local/nagios/libexec/check_rlm.py --help

CLI Reference

Argument	Type	Default	Description
port	positional int	(required)	RLM server port (1–65535)
server	positional str	(required)	RLM server hostname or IP address
feature	positional str	(required)	License feature name to check
--mode	choice	status	Check mode: status, expiry, or usage
--rlmutil-path	str	rlmutil	Path to the rlmutil binary
--isv	str	(none)	ISV server name to query
--warning-days	int	60	Warning threshold in days (expiry mode)
--alert-days	int	30	Critical threshold in days (expiry mode)
--warn-pct	float	80	Warning percentage threshold (usage mode)
--crit-pct	float	90	Critical percentage threshold (usage mode)
--timeout	int	10	Timeout in seconds for rlmutil execution (1–300)
--output-format	choice	standard	Output format: standard or json
--log-file	str	(none)	File path for structured logging output

Usage Examples

Status Check

Verify that a license feature is available for checkout:

./check_rlm.py 5053 license-server converge_gui --mode status --isv csci

Expected output:

OK - converge_gui can be checked out

Expiry Check

Monitor how many days remain until the license expires:

./check_rlm.py 5053 license-server converge_gui --mode expiry --isv csci --warning-days 90 --alert-days 30

Expected output:

OK - Feature 'converge_gui' expires in 222 days | days_until_expiry=222;;;;

Usage Check

Monitor the percentage of license seats currently in use:

./check_rlm.py 5053 license-server converge_gui --mode usage --isv csci --warn-pct 80 --crit-pct 95

Expected output:

OK - Feature 'converge_gui': 3/25 licenses in use (12.0%) | licenses_total=25;;;; licenses_used=3;;;; licenses_available=22;;;; utilization_pct=12.0%;80;95;0;100

Specifying an ISV Server

Scope the query to a specific ISV server:

./check_rlm.py 5053 license-server converge_gui --mode status --isv csci

JSON Output

Use --output-format json to produce machine-readable output:

./check_rlm.py 5053 license-server converge_gui --mode usage --isv csci --warn-pct 80 --crit-pct 95 --output-format json

Expected output:

{"status": "OK", "exit_code": 0, "message": "Feature 'converge_gui': 3/25 licenses in use (12.0%)", "performance_data": {"licenses_total": 25, "licenses_used": 3, "licenses_available": 22, "utilization_pct": 12.0}, "check_mode": "usage"}

The JSON object always contains:

Field	Type	Description
status	string	One of OK, WARNING, CRITICAL, UNKNOWN
exit_code	int	Nagios exit code (0–3)
message	string	Human-readable status message
performance_data	object	Metrics as key-value pairs
check_mode	string	The check mode that was executed

Logging

Enable structured file logging with --log-file:

./check_rlm.py 5053 license-server converge_gui --mode status --isv csci --log-file /var/log/check_rlm.log

Log entries are written in append mode, one per line:

2024-01-15T10:30:00+00:00 INFO [license-server:5053/converge_gui/status] Check starting
2024-01-15T10:30:01+00:00 INFO [license-server:5053/converge_gui/status] Check completed: OK (exit_code=0)

• Timestamps are ISO 8601 with timezone offset
• Levels: DEBUG, INFO, WARNING, ERROR
• Log file is created automatically if it does not exist
• Write failures are silently ignored — logging never causes the check to fail

Nagios XI CCM Integration

Command Definitions

Configure the following commands in Nagios XI Core Config Manager (CCM) under Commands.

check_rlm_status

Command Name: check_rlm_status
Command Line: $USER1$/check_rlm.py $ARG1$ $HOSTADDRESS$ $ARG2$ --mode status

Macro	Purpose
$ARG1$	Port
$ARG2$	Feature
$ARG3$	ISV server name (optional)

To include the optional ISV argument, use this command line instead:

$USER1$/check_rlm.py $ARG1$ $HOSTADDRESS$ $ARG2$ --mode status --isv $ARG3$

check_rlm_expiry

Command Name: check_rlm_expiry
Command Line: $USER1$/check_rlm.py $ARG1$ $HOSTADDRESS$ $ARG2$ --mode expiry --warning-days $ARG3$ --alert-days $ARG4$

Macro	Purpose
$ARG1$	Port
$ARG2$	Feature
$ARG3$	Warning days threshold
$ARG4$	Alert (critical) days threshold
$ARG5$	ISV server name (optional)

To include the optional ISV argument:

$USER1$/check_rlm.py $ARG1$ $HOSTADDRESS$ $ARG2$ --mode expiry --warning-days $ARG3$ --alert-days $ARG4$ --isv $ARG5$

check_rlm_usage

Command Name: check_rlm_usage
Command Line: $USER1$/check_rlm.py $ARG1$ $HOSTADDRESS$ $ARG2$ --mode usage --warn-pct $ARG3$ --crit-pct $ARG4$

Macro	Purpose
$ARG1$	Port
$ARG2$	Feature
$ARG3$	Warning percentage threshold
$ARG4$	Critical percentage threshold
$ARG5$	ISV server name (optional)

To include the optional ISV argument:

$USER1$/check_rlm.py $ARG1$ $HOSTADDRESS$ $ARG2$ --mode usage --warn-pct $ARG3$ --crit-pct $ARG4$ --isv $ARG5$

Service Definition Examples

Status Service

define service {
    use                 generic-service
    host_name           license-server
    service_description RLM Status - converge_gui
    check_command       check_rlm_status!5053!converge_gui!csci
    check_interval      5
    retry_interval      1
}

Expiry Service

define service {
    use                 generic-service
    host_name           license-server
    service_description RLM Expiry - converge_gui
    check_command       check_rlm_expiry!5053!converge_gui!csci!90!30
    check_interval      1440
    retry_interval      60
}

Usage Service

define service {
    use                 generic-service
    host_name           license-server
    service_description RLM Usage - converge_gui
    check_command       check_rlm_usage!5053!converge_gui!csci!80!95
    check_interval      5
    retry_interval      1
}

Development

Running Tests

Install test dependencies and run the test suite:

pip install -r requirements-dev.txt
pytest

The test suite uses Hypothesis for property-based testing and pytest as the test runner.

Test Structure

tests/
├── test_parser.py           # Round-trip property + parser edge cases
├── test_check_expiry.py     # Expiry threshold property + examples
├── test_check_usage.py      # Usage threshold property + examples
├── test_check_status.py     # Status check examples and edge cases
├── test_output_format.py    # Nagios format property + JSON property + examples
├── test_cli.py              # Argument parsing and validation
├── test_invoke.py           # rlmutil invocation (mocked subprocess)
└── test_logging.py          # Logger behavior