Prerequisites

The only prerequisite for setting up is installing the curl command. curl is a versatile tool used in Linux systems to transfer data from or to a server, supporting a variety of protocols such as HTTP, HTTPS, FTP, and more. It’s commonly used to download files, make API requests, or test network connections. To install curl we will need sudo or root permissions and use the command:

sudo apt install curl

As long as you get some form of output you now have curl installed.

Step 1: Run Commands Listed in Log Server

The exact commands we need to use in our instance of Ubuntu 22 are listed inside of Nagios LS, so we will be going there and looking at the commands needed. To do this we will want to add a log source, specifically a Linux source. We will want to click the circled area in the image below and select to add a Linux source.

Now there are instructions here, we will be going over them as well as their intended output. The first command is:

curl -sS -O http://<Nagios LS IP address>/nagioslogserver/scripts/setup-linux.sh

This command downloads the setup-linux.sh script from the Nagios Log Server URL and ensures it retains its original filename. Since the -sS flags suppress normal output, you won’t see anything unless there’s an error. If the download completes without issues, you can proceed to the next step by running the script with the following command:

sudo bash setup-linux.sh -s <Nagios LS IP Address> -p 5544

This should give us the following output:

With this it is all set up and should be sending Logs to Nagios Log Server.

Step 2: Verify Logs

Next, we need to verify that the Log Server is successfully receiving logs, and this step is straightforward. All you need to do is enter the IP address of your Ubuntu 22 host where it prompts you to ‘Verify Incoming Logs.’ This will confirm that the logs from your host are being properly sent to and received by the Log Server, ensuring everything is functioning as expected.

As you can see, the message confirms that logs are being received from our new host. This means that all the setup steps have been completed successfully, and Nagios Log Server is now properly receiving logs from the newly added host.

Conclusion

By following these steps, you’ve successfully set up Nagios Log Server on your Ubuntu 22 system, allowing you to capture and analyze logs efficiently. The process of configuring your server, running the necessary commands, and verifying log reception ensures that Nagios LS is fully operational, giving you the tools to monitor and manage your system’s health and security.

Now that your log monitoring is set up, you may want to explore additional monitoring methods for a more comprehensive approach. For system performance and resource monitoring, consider setting up NCPA on Ubuntu 22, a flexible agent that integrates seamlessly with Nagios XI. Alternatively, you can also use SNMP on Ubuntu 22 for monitoring with Nagios XI.

Prerequisites

• A working instance of Nagios XI
• A internet connection

Step 1: Install SNMP Daemon onto Ubuntu 22

To start, we need to install the SNMP Daemon (snmpd) on Ubuntu. The SNMP Daemon is responsible for allowing SNMP-enabled tools, like Nagios XI, to collect and manage data from the system. First, update your package lists with the following command:

sudo apt update

This command updates the local package database to ensure we have the latest information about available software packages. After the update is complete, install snmpd by running the following command:

sudo apt install snmpd

For testing purposes, we’ll also install the snmp package. This is primarily needed for running the snmpwalk command, which helps us verify the configuration locally. To install it, enter the following command:

sudo apt install snmp

Step 2: Configure SNMP

Now that it is installed, we need to configure it, as it is currently not configured, we will not be able to pull any information from the device. We need to edit the snmp.conf file, to do this use the command:

sudo nano /etc/snmp/snmpd.conf

We are looking for a few sections in this, first thing we want to do is find the agentadress section.

You can change this to match the IP address of your instance of Nagios XI for greater security, but if you use what’s listed above, it will work, it will allow the wizard we are using to recognize and access it through SNMP. Now we do want snmpwalk to access this, we need to change the view section now.

These SNMP view definitions specify which parts of the MIB tree are accessible to users. The first line grants access to standard system-related information (under .1.3.6.1.2.1), while the second allows access to enterprise-specific objects (under .1.3.6.1.4.1), thereby controlling the visibility of SNMP data for monitoring and management purposes. Next, the rocommunity line defines the read-only community string for SNMP access, which acts as a password for SNMP clients to retrieve data from the SNMP daemon. In this example, we will be using the default community string “public” for simplicity, though for enhanced security, it’s recommended to replace it with a more secure word or phrase of your choice.

Step 3: Restart the Service

The next step is to restart the SNMP service so that the changes take effect. To do this, simply run the following command:

sudo service snmpd restart

This will restart the SNMP service, and you shouldn’t receive any output if everything is configured correctly. If you do get output, it likely indicates an error in the snmpd.conf file—most often a typo in one of the lines. Please review the file and check for any mistakes. Once that’s sorted, we’ll want to verify that our configurations are working. To do this, we can use the snmpwalk command locally. Alternatively, if you have access to the Nagios XI Linux host, you can perform the test from there as well. The command to use is:

snmpwalk -v 2c -c <rocommunity> localhost/<ip address>

You should receive a very long output, whether you’re testing locally or through the Nagios XI Linux host. If this happens, it confirms that SNMP is set up correctly. It’s even better if you’re able to get it working through the Nagios XI Linux host, as this will verify that the system is correctly receiving and processing SNMP data for monitoring.

Step 4: Set Up on Nagios XI

With everything set up, we can now configure monitoring through Nagios XI using the Linux SNMP Wizard. You’ll need to enter the IP address of your Ubuntu device along with the rocommunity string. The SNMP daemon supports multiple versions of SNMP, so the default settings for both the SNMP version and port should work perfectly.

After configuring the settings, you can choose the hostname and select any services you want to monitor through SNMP. Once these steps are completed, your host will be set up for monitoring. By clicking on the hostname, you’ll see that it is being actively monitored and collecting data for the selected services.

Conclusion

With these steps, we’ve successfully set up Ubuntu 22 to be monitored using SNMP with Nagios XI. If you encounter any issues, please refer to the Nagios Support Forum for assistance. Alternatively, if you prefer to monitor using the Nagios Cross-Platform Agent, you can find more information here.

Step 1 Method 1: Installing via the Repository (Recommended)

The preferred method for installing NCPA is through the repository. This approach involves a series of simple steps that can all be executed from the command line.

Add the Nagios repository to your sources list: To do this, execute the following command:

echo "deb https://repo.nagios.com/deb/$(lsb_release -cs) /" > /etc/apt/sources.list.d/nagios.list

This command will add the repository to your system, ensuring you have access to the NCPA package.

Add the GPG key for the repository: The GPG key is required to verify the integrity of the packages you’ll download. You might encounter a warning saying that the command used is deprecated, but don’t worry—it will still function correctly. To add the GPG key, use:

wget -qO - https://repo.nagios.com/GPG-KEY-NAGIOS-V3 | apt-key add -

If successful, you should see the message OK, confirming the key was added correctly.

Update your package list: Now that the repository and key are set up, update your package lists:

apt-get update

Install the NCPA package: With the update complete, you can now install NCPA using the following command:

apt-get install ncpa

Step 1 Method 2: Downloading the Package

If for some reason the repository method doesn’t work, you can manually download and install the NCPA package. Follow these steps:

Download the latest NCPA package: Start by downloading the NCPA .deb package with the following command:

wget https://assets.nagios.com/downloads/ncpa3/ncpa-latest-1.amd64.deb

Install the downloaded package: After the package is downloaded, install it using:

sudo dpkg -i ncpa-latest-1.amd64.deb

As long as you get the above out put or something similar, you have successfully installed NCPA.

Step 2: Configure NCPA

After installing NCPA, the agent will work out of the box, but it’s highly recommended to configure the API token for added security. Without this step, the default token will be used, which might not be ideal for your environment. Enter the following into your command line:

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

In the configuration file, look for the line that reads: community_string = mytoken.

Replace mytoken with a secure token of your choice. After updating the token, press CTRL + X, then press Y to confirm the changes, and hit Enter to save the file. We want to use the token we made so there is one final step, which is to restart our NCPA. At the moment its API token that will be accepted is still the default token. We want it to use the newly created one. To do this we enter the following command:

systemctl restart ncpa

This will restart the service, and NCPA will now use the newly configured token.

Step 3: Configuring Firewall

If you’re running a firewall on your system, you’ll need to allow traffic on port 5693, which is used by NCPA. For Ubuntu systems with UFW (Uncomplicated Firewall) enabled, follow these steps to configure the firewall and allow NCPA traffic:

Create the directory for UFW application profiles: First, create the necessary directory where UFW can store application profiles:

sudo mkdir -p /etc/ufw/applications.d

Create a custom application profile for NCPA: Next, set up a custom profile for NCPA by running the following commands:

sudo sh -c "echo '[NCPA]' > /etc/ufw/applications.d/ncpa"
sudo sh -c "echo 'title=Nagios Cross Platform Agent' >> /etc/ufw/applications.d/ncpa"
sudo sh -c "echo 'description=Nagios Monitoring Agent' >> /etc/ufw/applications.d/ncpa"
sudo sh -c "echo 'ports=5693/tcp' >> /etc/ufw/applications.d/ncpa"

Allow NCPA traffic through the firewall: Once the profile is set up, allow NCPA through the firewall with:

sudo ufw allow NCPA

Reload the firewall to apply the changes: Finally, reload UFW to apply the changes:

sudo ufw reload

Step 4(Optional): Confirm NCPA installation

This step is straightforward. Simply open a web browser and navigate to https://<host-ip-address>:5693.

This will bring you to the login page, where you can enter your token. The purpose of this step is to verify that the NCPA is up and running, that it is reading the token correctly, and that remote access is functional.

Step 5: Configuring on Nagios XI

The final step involves configuring Nagios XI. To do this, navigate to the Configuration Wizards section in Nagios and select the NCPA Wizard.

1. Navigate to the Configuration Wizards section in Nagios XI and select the NCPA Wizard.
2. Enter the necessary information, including the IP address, the token, and the system type (Ubuntu in this case).
3. During the setup, you will be prompted to choose a name for your host and select the services you want to monitor with NCPA.

Once the setup is complete, the new host will appear in your monitoring dashboard. You can navigate to the Host Status section to confirm that it is being monitored properly.

Conclusion

By following this guide, you have successfully installed and configured the Nagios Cross-Platform Agent (NCPA) on Ubuntu 22. You are now able to monitor the system using Nagios XI. If any issues are encountered, we recommend using the Nagios Support Forum.