How to Set Up SNMP on SUSE Linux Enterprise Server (SLES) 15 and Monitor with Nagios XI

SUSE Linux Enterprise Server (SLES) 15 is a powerful and reliable platform for running enterprise applications and managing IT infrastructure. One of the essential tools for monitoring and managing network devices is Simple Network Management Protocol (SNMP). This guide walks you through the process of installing and configuring SNMP on SLES 15 and then integrating it into Nagios XI, with a focus on the required steps for a registered copy of the operating system.

Prerequisites

Before you begin, ensure that you meet the following prerequisites:

• A registered copy of SLES 15: Registration is necessary to access official SUSE repositories and receive support. If your system is not registered, you may not be able to install SNMP via official repositories.
• Root or sudo access: You will need root access or sudo privileges to install software and configure SNMP.

Step 1: Register SLES 15

If you haven’t registered your system yet, you can do so by running the following command:

sudo SUSEConnect --registration-url https://scc.suse.com

You will need to provide your SUSE Customer Center credentials (your username and password). Registration allows you to access SUSE’s official repositories, which is necessary for installing SNMP and other packages.

Once registered, refresh the repositories:

sudo zypper refresh

Step 2: Install SNMP Packages

With a registered system, you can now install SNMP and its required packages using zypper, SUSE’s package management tool.

sudo zypper install net-snmp

This will install the necessary packages to get SNMP up and running on your SLES 15 system.

Step 3: Start and Enable SNMP Service

After installing the SNMP packages, you need to enable and start the snmpd service to begin monitoring your system.

1. Enable the service to start at boot:

sudo systemctl enable snmpd

2. Start the SNMP service:

sudo systemctl start snmpd

3. Check the status of the SNMP service:

sudo systemctl status snmpd

You should see output indicating that the service is active and running.

Step 4: Configure SNMP

SNMP configuration can be customized by editing the snmpd.conf file, located at:

sudo nano /etc/snmp/snmpd.conf

Here, you can modify settings like:

• Community strings (for access control)
• Security settings (to secure SNMP data)
• Other SNMP parameters for device management

Look for the rocommunity public line and modify it to allow your Nagios servers IP address. Replace public with a community string that you can remember and then replace 127.0.0.1 to your Nagios server IP address.

For example this is what I did:

Note: If you want to allow access from any system (not recommended for security), use:

rocommunity myCommunityString default

Once you are done editing your file, save and exit.

Step 5: Test SNMP Configuration

Once SNMP is installed and configured, test it using snmpwalk on your Nagios XI server.

Test from Your Monitoring Server (e.g., Nagios)

If running the test from your Nagios server, replace <SUSE_SERVER_IP> with your SUSE server’s IP:

snmpwalk -v 2c -c myCommunityString <SUSE_SERVER_IP>

If you see a lot of HOST-RESOURCES-MIB data, SNMP is working correctly!

Step 6: Monitor with Nagios

From your Nagios XI web interface home page, click on Run a Wizard.

Then, scroll until you find the Linux SNMP wizard.

Then enter the IP address of your SUSE 12 machine. Leave the SNMP version at 2c and the SNMP Port at 161. The SNMP Community is where you will enter the community string you created in the conf file in Step 2.

Now, you can change any settings you need and choose which metrics you would like to monitor.

By default, you will be monitoring some basic services. When you are done configuring your settings and choosing SNMP services to monitor you can hit Next, and then Finish with Defaults.

Congratulations! You have successfully installed and configured SNMP on SUSE 15 and integrated it with Nagios. Your server is now actively monitored for performance metrics like CPU, memory, and uptime.