Your first Network Ansible Playbook

For this challenge we will examine an already created Ansible Playbook

Ansible Network Automation Basics

The lab objective is to use Ansible Automation to update the configuration of a Cisco CSR router. This exercise will not create an Ansible Playbook, but use an existing one that has been provided.

This exercise will cover:

examining an existing Ansible Playbook
executing an Ansible Playbook on the command line using the ansible-navigator command
check mode (the --check parameter)
verbose mode (the --verbose or -v parameter)

Ansible Playbook

What makes up an Ansible Playbook?

Ansible Plays

What am I automating?

---
- name: configure network devices
  hosts: network
  become: yes

What are they?
- Top level specification for a group of tasks.
  
  Will tell that play which hosts it will execute on and control behavior such as fact gathering or privilege level.
- Building blocks for playbooks
  
  Multiple plays can exist within an Ansible playbook

Ansible Modules

The "tools in the toolkit"

- name: ensure that the desired snmp strings are present
  cisco.ios.config:
    commands:
      - snmp-server community ansible-public RO
      - snmp-server community ansible-private RW
    save_when: modified

What are they?

Parametrized components with internal logic, representing a single step to be done. The modules "do" things in Ansible.

Ansible Plugins

What are they?

Plugins are pieces of code that augment Ansible’s core functionality. Ansible uses a plugin architecture to enable a rich, flexible, and expandable feature set.
```
{{ some_variable | `to_nice_json` }}
{{ some_variable | `to_nice_yaml` }}
```

Ansible Inventory

What are they?

List of systems in your infrastructure that automation is executed against

[web]
webserver1.example.com
webserver2.example.com

[db]
dbserver1.example.com

[switches]
leaf01.internal.com
leaf02.internal.com

Ansible Roles

What are they?
```
---
- name: install and start apache
  hosts: network
  roles:
    - network.toolkit.backup
```
Group your tasks and variables of your automation in a reusable structure. Write roles once, and share them with others who have similar challenges in front of them.

Ansible Content Collections

Simplified and consistent content delivery

What are they?

Collections are a directory structure containing automation content such as: - Modules - Playbooks - Roles - Plugins - Docs - Tests

Lets get started

That is the end of of your lab briefing!

Step 1 - Examine Ansible Playbook

Open the playbook.yml in the code-server tab.

We will explore in detail the components of an Ansible Playbook in the next exercise. It is suffice for now to see that this playbook will run two Cisco IOS-XE commands:
```
snmp-server community ansible-public RO
snmp-server community ansible-private RW
```

Step 2 - Execute Ansible Playbook

Open the terminal tab and run the following command:

ansible-navigator run playbook.yml --mode stdout

--mode stdout - By default ansible-navigator will run in interactive mode. The default behavior can be modified by modifying the ansible-navigator.yml configuration file. As playbooks get longer and involve multiple hosts the interactive mode allows you to "zoom in" on data in real-time, filter it, and navigate between various Ansible components. Since this task only ran one task on one host the stdout is sufficient.

Step 3 - Verify configuration on router

Login to the cisco device and run the show run command to check the configuration:
```
ssh cisco
```
```
show running | i snmp
```
Output should be similar to the following:
```
snmp-server community ansible-public RO
snmp-server community ansible-private RW
```
```
exit
```