Exercise 1.2 - Adding nodes to F5 BIG-IP

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Table of Contents

• 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.

Do not close the editor yet.

Step 3

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

  tasks:

  - name: CREATE NODES
    bigip_node:
      provider:
        server: "{{private_ip}}"
        user: "{{ansible_user}}"
        password: "{{ansible_ssh_pass}}"
        server_port: 8443
        validate_certs: no
      host: "{{hostvars[item].ansible_host}}"
      name: "{{hostvars[item].inventory_hostname}}"
    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 provider: parameter is a group of connection details for the BIG-IP.
• The user: "" parameter tells the module the username to login to the F5 BIG-IP device with
• The password: "" 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.

Save the file and exit out of editor.

Step 4

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

[student1@ansible ~]$ ansible-playbook bigip-node.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/

Login information for the BIG-IP:

• username: admin
• password: admin

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

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