Exercise 1.2 - Adding nodes to F5 BIG-IP

Objective
Guide
Playbook Output
Solution

Objective

Demonstrate use of the BIG-IP node module to add two RHEL (Red Hat Enterprise Linux) web servers as nodes for the BIG-IP load balancer.

Guide

Step 1:

Using your text editor of choice create a new file called bigip-node.yml.

[student1@ansible ~]$ nano bigip-node.yml

vim and nano are available on the control node, as well as Visual Studio and Atom via RDP

Step 2:

Enter the following play definition into bigip-node.yml:

---
- name: BIG-IP SETUP
  hosts: lb
  connection: local
  gather_facts: false

The --- at the top of the file indicates that this is a YAML file.
The hosts: lb, indicates the play is run only on the lb group. Technically there only one F5 device but if there were multiple they would be configured simultaneously.
connection: local tells the Playbook to run locally (rather than SSHing to itself)
gather_facts: false disables facts gathering. We are not using any fact variables for this playbook.

Step 3

Next, add the first task. This task will use the bigip_node module configure the two RHEL web servers as nodes on the BIG-IP F5 load balancer.

---
- name: BIG-IP SETUP
  hosts: lb
  connection: local
  gather_facts: false

  tasks:

  - name: CREATE NODES
    bigip_node:
      server: "{{private_ip}}"
      user: "{{ansible_user}}"
      password: "{{ansible_ssh_pass}}"
      server_port: "8443"
      host: "{{hostvars[item].ansible_host}}"
      name: "{{hostvars[item].inventory_hostname}}"
      validate_certs: "no"
    loop: "{{ groups['webservers'] }}"

A loop will repeat a task on a list provided to the task. In this case it will loop twice, once for each of the two web servers.

name: CREATE NODES is a user defined description that will display in the terminal output.
bigip_node: tells the task which module to use. Everything except loop is a module parameter defined on the module documentation page.
The server: "" parameter tells the module to connect to the F5 BIG-IP IP address, which is stored as a variable private_ip in inventory
The user: "" parameter tells the module the username to login to the F5 BIG-IP device with
Thepassword: "" parameter tells the module the password to login to the F5 BIG-IP device with
The server_port: 8443 parameter tells the module the port to connect to the F5 BIG-IP device with
The host: "" parameter tells the module to add a web server IP address already defined in our inventory.
The name: "" parameter tells the module to use the inventory_hostname as the name (which will be host1 and host2).
The validate_certs: "no" parameter tells the module to not validate SSL certificates. This is just used for demonstration purposes since this is a lab.
loop: tells the task to loop over the provided list. The list in this case is the group webservers which includes two RHEL hosts.

Step 4

Run the playbook - exit back into the command line of the control host and execute the following:

[student1@ansible ~]$ ansible-playbook bigip-facts.yml

Playbook Output

The output will look as follows.

[student1@ansible]$ ansible-playbook bigip-node.yml

PLAY [BIG-IP SETUP] ************************************************************

TASK [CREATE NODES] ************************************************************
changed: [f5] => (item=host1)
changed: [f5] => (item=host2)

PLAY RECAP *********************************************************************
f5                         : ok=1    changed=1    unreachable=0    failed=0

Solution

The finished Ansible Playbook is provided here for an Answer key. Click here: bigip-node.yml.

Verifying the Solution

Login to the F5 with your web browser to see what was configured. Grab the IP information for the F5 load balancer from the lab_inventory/hosts file, and type it in like so: https://X.X.X.X:8443/

The list of nodes can be found by navigating the menu on the left. Click on Local Traffic-> then click on Nodes. f5web

You have finished this exercise. Click here to return to the lab guide

ANSIBLE