Exercise 2.0 - Disabling a pool member

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Table of Contents

Objective
Guide
Playbook Output
Solution

Objective

For this last exercise instead of prescriptive step-by-step walkthrough a framework of objectives with hints for each step will be provided.

Demonstrate the removal of a node from the pool. Build a Playbook that:

Retrieve Facts from BIG-IP for the pools present on the BIG-IP (in our example only one pool is present)
Display pools available
Store the pool name as a fact
Display all the pool members that belong to the pool => IP and port information to the terminal window
Prompt the user to disable a particular member or disable all members of the pool
Force the appropriate pool members offline

Guide

Step 1:

Using VSCode create a new file called disable-pool-member.yml by clicking the new file icon in the left pane.

Step 2:

Enter the following play definition into disable-pool-member.yml:

---
- name: Disabling a pool member
  hosts: lb
  connection: local
  gather_facts: false

Step 3

Add a tasks section and then set a fact for the provider. Once you set the provider you can re-use this key in future tasks instead of giving the server/user/password/server_port and validate_certs info to each task.

  tasks:
    - name: Setup provider
      set_fact:
        provider:
          server: "{{private_ip}}"
          user: "{{ansible_user}}"
          password: "{{ansible_password}}"
          server_port: 8443
          validate_certs: false

Now in the next task you can use provider as follows:

      f5networks.f5_modules.bigip_device_info:
        provider: "{{provider}}"
        gather_subset:
        - ltm-pools

You DO NOT need to pass the server_ip/user/password etc. for each module going forward

Step 4

Next, add a task for the objective listed below:

Retrieve Facts from BIG-IP for the subset ltm-pools

HINT: Try using the bigip_device_info module from Exercise 1.1

Step 5

Next, add a task for the objective listed below:

Display the pool information to the terminal window

HINT: Find a way to loop on the output from the above step. Remember to also use the debug module

Step 6

Next, add a task for the objective listed below:

Store the pool name as a fact

HINT: An easy way to set fact variables within a Playbook dynamically is using the set_fact module

Step 7

Next, add a task for the objective listed below:

Display members belonging to the pool

HINT: Remember to use the debug and refer Exercise 1.4

Step 8

Next, add a task for the objective listed below:

Disable all members belonging to the pool

HINT: Remember to use BIG-IP pool member module

Step 9

Run the playbook - Go back to the Terminal on VS Code server and execute the following:

[student1@ansible ~]$ ansible-navigator run disable-pool-member.yml --mode stdout

Playbook Output

The output will look as follows.

[student1@ansible-1 ~]$ ansible-navigator run disable-pool-member.yml --mode stdout

PLAY [Disabling a pool member] *************************************************

TASK [Setup provider] **********************************************************
ok: [f5]

TASK [Query BIG-IP facts] ******************************************************
ok: [f5]

TASK [Display Pools available] *************************************************
ok: [f5] => (item=http_pool) => {
    "msg": "http_pool"
}

TASK [Store pool name in a variable] *******************************************
ok: [f5] => (item=None)
ok: [f5]

TASK [Show members belonging to pool http_pool] ********************************
ok: [f5] => (item=node1:80) => {
    "msg": "node1:80"
}
ok: [f5] => (item=node2:80) => {
    "msg": "node2:80"
}

TASK [Disable ALL pool members] ************************************************
ok: [f5] => (item=node1:80)
ok: [f5] => (item=node2:80)

PLAY RECAP *********************************************************************
f5                         : ok=6    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

Solution

The solution will be provided by the instructor if you are stuck. The GUI should show something similar to the following with a black diamond indicating the specified node was forced offline.

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