6.4 KiB
Ansible Role: cnos_conditional_template_sample - Manages switch configuration using templates with respect to conditions specified in the inventory
This role is an example of using the cnos_conditional_template.py Lenovo module in the context of CNOS switch configuration. This module allows you to work with the running configuration of a switch. It provides a way to execute a set of CNOS commands on a switch by evaluating the current running configuration and executing the commands only if the specific settings have not been already configured.
The configuration source can be a set of commands or a template written in the Jinja2 templating language.
This module functions the same as the cnos_template.py module. The only exception is that the following inventory variable can be specified: condition =
When this inventory variable is specified as the variable of a task, the template is executed for the network element that matches the flag string.
Usually, templates are used when commands are the same across a group of network devices. When there is a requirement to skip the execution of the template on one or more devices, it is recommended to use this module.
The results of the operation can be viewed in results directory.
For more details, see Lenovo modules for Ansible: cnos_conditional_template.
Requirements
- Ansible version 2.2 or later (Ansible installation documentation)
- Lenovo switches running CNOS version 10.2.1.0 or later
- an SSH connection to the Lenovo switch (SSH must be enabled on the network device)
Role Variables
Available variables are listed below, along with description.
The following are mandatory inventory variables:
| Variable | Description |
|---|---|
username |
Specifies the username used to log into the switch |
password |
Specifies the password used to log into the switch |
enablePassword |
Configures the password used to enter Global Configuration command mode on the switch (this is an optional parameter) |
hostname |
Searches the hosts file at /etc/ansible/hosts and identifies the IP address of the switch on which the role is going to be applied |
deviceType |
Specifies the type of device from where the configuration will be backed up (g8272_cnos - G8272, g8296_cnos - G8296) |
condition |
If condition=<flag string> is specified in the inventory file against any device, the template execution is done for that device in case it matches the flag setting for that task |
The values of the variables used need to be modified to fit the specific scenario in which you are deploying the solution. To change the values of the variables, you need to visits the vars directory of each role and edit the main.yml file located there. The values stored in this file will be used by Ansible when the template is executed.
The syntax of main.yml file for variables is the following:
<template variable>:<value>
You will need to replace the <value> field with the value that suits your topology. The <template variable> fields are taken from the template and it is recommended that you leave them unchanged.
| Variable | Description |
|---|---|
flag |
If a task needs to be executed, you have to set the flag the same as it is specified in the inventory for that device |
commandfile |
Specifies the path to the CNOS command file which needs to be applied |
Dependencies
- username.iptables - Configures the firewall and blocks all ports except those needed for web server and SSH access.
- username.common - Performs common server configuration.
- cnos_conditional_template.py - This modules needs to be present in the library directory of the role.
- cnos.py - This module needs to be present in the PYTHONPATH environment variable set in the Ansible system.
- /etc/ansible/hosts - You must edit the /etc/ansible/hosts file with the device information of the switches designated as leaf switches. You may refer to cnos_conditional_template_sample_hosts for a sample configuration.
Ansible keeps track of all network elements that it manages through a hosts file. Before the execution of a playbook, the hosts file must be set up.
Open the /etc/ansible/hosts file with root privileges. Most of the file is commented out by using #. You can also comment out the entries you will be adding by using #. You need to copy the content of the hosts file for the role into the /etc/ansible/hosts file. The sample hosts file for the role is located in the main directory.
[cnos_conditional_template_sample]
10.241.107.39 username=<username> password=<password> deviceType=g8272_cnos condition=pass
10.241.107.40 username=<username> password=<password> deviceType=g8272_cnos
Note: You need to change the IP addresses to fit your specific topology. You also need to change the <username> and <password> to the appropriate values used to log into the specific Lenovo network devices.
Example Playbook
To execute an Ansible playbook, use the following command:
ansible-playbook cnos_conditional_template_sample.yml -vvv
-vvv is an optional verbos command that helps identify what is happening during playbook execution. The playbook for each role is located in the main directory of the solution.
- name: Module to do some template configurations
hosts: cnos_conditional_template_sample
gather_facts: no
connection: local
roles:
- cnos_conditional_template_sample
License
Copyright (C) 2017 Lenovo, Inc.
This file is part of Ansible
Ansible is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
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