Using Kubernetes dynamic inventory plugin

• Kubernetes dynamic inventory plugin

  • Requirements
• Using vaulted configuration files

Kubernetes dynamic inventory plugin

The best way to interact with your Pods is to use the Kubernetes dynamic inventory plugin, which dynamically queries Kubernetes APIs using kubectl command line available on controller node and tells Ansible what Pods can be managed.

Requirements

To use the Kubernetes dynamic inventory plugins, you must install Kubernetes Python client, kubectl and OpenShift Python client on your control node (the host running Ansible).

$ pip install kubernetes openshift

Please refer to Kubernetes official documentation for installing kubectl on the given operating systems.

To use this Kubernetes dynamic inventory plugin, you need to enable it first by specifying the following in the ansible.cfg file:

[inventory]
enable_plugins = kubernetes.core.k8s

Then, create a file that ends in .k8s.yml or .k8s.yaml in your working directory.

The kubernetes.core.k8s inventory plugin takes in the same authentication information as any other Kubernetes modules.

Here’s an example of a valid inventory file:

plugin: kubernetes.core.k8s

Executing ansible-inventory --list -i <filename>.k8s.yml will create a list of Pods that are ready to be configured using Ansible.

You can also provide the namespace to gather information about specific pods from the given namespace. For example, to gather information about Pods under the test namespace you will specify the namespaces parameter:

plugin: kubernetes.core.k8s
connections:
- namespaces:
    - test

Using vaulted configuration files

Since the inventory configuration file contains Kubernetes related sensitive information in plain text, a security risk, you may want to encrypt your entire inventory configuration file.

You can encrypt a valid inventory configuration file as follows:

$ ansible-vault encrypt <filename>.k8s.yml
  New Vault password:
  Confirm New Vault password:
  Encryption successful

$ echo "MySuperSecretPassw0rd!" > /path/to/vault_password_file

And you can use this vaulted inventory configuration file using:

$ ansible-inventory -i <filename>.k8s.yml --list --vault-password-file=/path/to/vault_password_file