In this blog post we are going to show you how we can use the API Clients created for IP Fabric and NAGIOS. We are going to work on a simple scenario where we want to create hosts discovered by IP Fabric into NAGIOS XI.

There are already a few blogs on how to use IP Fabric’s API, so today we’re going to focus on using the API clients, which have been created to simplify interaction and data collection.

1.    How to get the API clients

First, you need to download the code in our GitLab repository: 2021-08-30-ipfabric-nagios-api-integration using your preferred method:

Cloning:

Download:

Inside the api_clients folder, you will see the existing API clients. We will have a look at ipf and nagios, to understand how to use them.

Before looking at each API client, we need to define some requirements to ensure everything will work as expected.

1.1 Pre-requisites

For this blog post, I will be using iPython for its powerful interactive shell, but you can use Python3. To use the Nagios and IPF api client, you need to install the HTTPX library, and we would recommend using the rich library as well.

How to install iPython:

1.2 IP Fabrics’s API client – Overview

To start using the API Client, you need to provide the information regarding the IP Fabric server and the token. 

To create the token on IP Fabric, go to Settings/API Tokens and create a new token:

You need to create environment variables:

We can now run ipython to create the IP Fabric client:

1.2.1 Class: IPFClient

Let’s explore the IPFClient class, which will interact with the IP Fabric server.

The Class ipf will be created using the environment variables you created above. To confirm it has worked correctly, you can look at the list of snapshots. This will confirm that we have access to the data from the IP Fabric server:

At the time of writing, this is the list of functions you can use within the IPFClient class:

• 'snapshot_list' – provide the list of snapshots
• 'site_list' – provide the list of sites
• 'device_list' – provide the list of devices
• 'fetch_table' – return IP Fabric data from any table as a json

1.2.2 Class: IPFDevice

You can now assign a device to a variable which will allow you to access information for that specific device (IP address, hostname, site…)

1.3 NAGIOS XI API Client – Overview

Just like we did with IP Fabric, we need to ensure we have a valid token to use the Nagios XI API. To proceed, you need to go to your account setting (1) and generate an API key (2):

You also need to create the environment variables related to Nagios:

We can now run ipython to create the NAGIOS XI API client:

1.3.1 Class: NAGIOSClient

Let’s explore the NAGIOSClient class, which will interact with the NAGIOS server.

The Class nagios will be created using the environment variables you created above. To confirm it has worked correctly, you can look at the list of existing hosts. This will confirm that we have access to Nagios’ data:

At the time of writing, this is the list of functions you can use within the NAGIOSClient class:

• 'host_list' – provide the list of hosts
• 'hostgroup_list' – provide the list of hostgroups
• 'create_hostgroup' – create the hostgroup indicated, if not already present

1.3.2 Class: NAGIOSSensor

Using this class, you will be able to create a new host directly into Nagios. Here is how to proceed:

If you look at Nagios, you will now see under Hostgroup Overview the recently created host L45R10, inside the hostgroup “45 Ballpark”

This is brilliant, we can now interact with the API for IP Fabric and Nagios. In the next section we will see how we can use this to automatically populate devices in Nagios based on the information collected by IP Fabri

2. Creating Hosts in NAGIOS using the data from IP FABRIC

In this part, we are going to take, for example, the following situation: you have decided to replace your previous monitoring system with Nagios, and you want to ensure all devices will be correctly added. How can you proceed?

• You could manually add each device, working with your CMDB, but what happens if that list is not 100% accurate, some IPs may have changed, devices were added or removed, and you are not aware.
• Second option, execute a script to create Nagios hosts using the data from IP Fabric, so you know it’s accurate and up-to-date. Let’s look at this option in more detail.

2.1 Create Nagios hosts using a Python script

You are about to witness how short the code to execute this is!

2.2 Important notes

Please ensure you have created the environment variable as mentioned previously in this blog:

An easy way to create the filter is to follow these steps:

1 - Go to Inventory/Devices

2 - Use any filter to get the list of devices you want to add into Nagios

3 - Click on the question mark “Table description”

4 - In the payload, find the “filters”, use this to create the variable filters in the python script. In our situation it becomes:

filters = {"siteName": ["like", "45"]}

3. Conclusion

You can learn more at www.ipfabric.io and also follow our company’s LinkedIn page or Blog, where we continually post new content.

For more information regarding existing and on-going integrations, join us on IP Fabric Community Slack.