How to Install Nagios Cross-Platform Agent (NCPA) on macOS Monterey

Prerequisites

Before starting, ensure you have:

• A macOS system running macOS 12 Monterey or later on Apple Silicon.
• Administrator privileges (sudo access).
• An active Nagios Core or Nagios XI server to receive monitoring data.
• Basic familiarity with the Terminal and command-line tools.

Step 1: Install Development Tools and Dependencies

Since we’re building NCPA from source, you’ll need Homebrew (a package manager) and some required dependencies.

1.1 Install Homebrew (if not already installed)

Open Terminal and run:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

On Apple Silicon, Homebrew installs to /opt/homebrew/. Add it to your PATH if prompted (instructions will appear after installation).

1.2 Install Required Dependencies

Install Python 3, OpenSSL, and Git using Homebrew:

brew install python3 openssl git

This installs Python 3.x (e.g., 3.11 or later), OpenSSL for secure communication, and Git for cloning the NCPA repository.

1.3 Verify Python Installation

Check the version to ensure it’s installed:

python3 --version

Step 2: Download NCPA Source Code

Nagios doesn’t provide a direct macOS package for NCPA, so we’ll clone it from GitHub.

2.1 Clone the NCPA Repository

Run the following command to clone the NCPA source code:

git clone https://github.com/NagiosEnterprises/ncpa.git
cd ncpa

This downloads the latest NCPA source (e.g., version 3.1.2 or newer if updated post-March 2025).

2.2 Optional: Check for Updates

If you want a specific version, use:

git checkout v3.1.2  # replace with the desired version tag

Otherwise, the master branch (default) is fine for the latest stable version.

Step 3: Build NCPA from Source

3.1 Install Python Dependencies

Before building, install the Python dependencies listed in the requirements.txt file:

pip3 install -r requirements.txt

This installs libraries like psutil, bottle, and other required modules.

3.2 Run the Build Script

Build the NCPA binary for macOS:

python3 build.py --platform macos

The --platform macos flag ensures macOS-specific adjustments. On Apple Silicon, Python and dependencies should automatically target ARM64. If there’s an issue with architecture, you can explicitly specify:

arch -arm64 python3 build.py --platform macos

3.3 Locate the Output

After a successful build, the executable and supporting files will be in a build subdirectory (e.g., build/ncpa). The folder name may vary based on the platform (e.g., build/ncpa-macos-arm64).

Step 4: Install NCPA

Now, move the built files to a standard location and set up the agent.

4.1 Copy Files to Installation Directory

To maintain consistency, copy the NCPA files to /usr/local/ncpa:

sudo mkdir -p /usr/local/ncpa
sudo cp -r build/ncpa/* /usr/local/ncpa/

Make sure to adjust the build/ncpa path if needed, based on your output.

4.2 Set Permissions

Ensure the files are executable:

sudo chmod +x /usr/local/ncpa/ncpa

Step 5: Configure NCPA

5.1 Edit the Configuration File

The main configuration file is usually located at /usr/local/ncpa/etc/ncpa.cfg. Open it with nano:

sudo nano /usr/local/ncpa/etc/ncpa.cfg

In the configuration file, set the API token (used for secure communication):

[general]
community_string = Str0ngT0k3n!

Restrict access to your Nagios server’s IP by updating the allowed_hosts section:

[general]
allowed_hosts = <Nagios_IP_address>

Save and exit (Ctrl+X, then Y to confirm, and Enter).

5.2 Test the Configuration

You can now test the NCPA agent:

sudo /usr/local/ncpa/ncpa

If it runs without errors (e.g., binding to port 5693), press Ctrl+C to stop it.

Step 6: Set Up NCPA as a Service

To ensure NCPA starts automatically on boot, you’ll need to create a launchd service file.

6.1 Create the Service File

Create the com.nagios.ncpa.plist file:

sudo nano /Library/LaunchDaemons/com.nagios.ncpa.plist

Paste the following content into the file:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>com.nagios.ncpa</string>
    <key>ProgramArguments</key>
    <array>
        <string>/usr/local/ncpa/ncpa</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
    <key>KeepAlive</key>
    <true/>
</dict>
</plist>

6.2 Load and Start the Service

Now, load and start the service with:

sudo launchctl load /Library/LaunchDaemons/com.nagios.ncpa.plist
sudo launchctl start com.nagios.ncpa

6.3 Verify Services

Check that NCPA is running by listing the services:

sudo launchctl list | grep ncpa

You should see the service listed along with its process IDs (PIDs).

Step 7: Verify NCPA Installation

7.1 Check the Web Interface

Open a browser and visit:

https://localhost:5693

Log in using the API token you set earlier (Str0ngT0k3n! or your custom value).

7.2 Test from Nagios Server

From your Nagios server, run:

curl -k https://<your_mac_ip>:5693/api

Step 8: Add NCPA to Nagios

On your Nagios XI web GUI:

• Navigate to Configuration Wizards.

• Select Mac OS X.

• Enter the IP address of your macOS system and the API token you created in the configuration file.
• Follow the wizard to select the system metrics you want to monitor.

• Click Finish to complete the setup.

Conclusion

By following these steps, you have successfully installed the Nagios Cross-Platform Agent (NCPA) on macOS Monterey for Apple Silicon. Your Nagios monitoring server will now be able to collect system metrics and monitor your macOS system in real time.

For further support, refer to:

• Nagios Support Forum: https://support.nagios.com/forum/
• Nagios Knowledge Base: https://support.nagios.com/kb/