Exercise 2.2: Using a combination of modules to perform a graceful rollback

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Table of Contents

• Objective
• Guide
• Playbook Output
• Solution

Objective

Demonstrate use of the different modules to perform a rollback of the configuration on the BIG-IP.

Guide

Step 1

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

[student1@ansible ~]$ nano bigip-error-handling.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-error-handling.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 F5 BIG-IP device
• 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

Add a tasks section with a set_fact for setting the provider values

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

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

Step 4

Next, add the block stanza and the first task. The first task will be the bigip_node as performed in Exercise 1.2 - Adding nodes to F5 BIG-IP.

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

  tasks:
    - name: Setup provider
      set_fact:
      provider:
        server: "{{private_ip}}"
        user: "{{ansible_user}}"
        password: "{{ansible_password}}"
        server_port: "8443"
        validate_certs: "no"

    - name: SETUP AND GRACEFUL ROLLBACK BIG-IP CONFIGURATION
      block:
        - name: CREATE NODES
          f5networks.f5_modules.bigip_node:
            provider: "{{provider}}"
            host: "{{hostvars[item].ansible_host}}"
            name: "{{hostvars[item].inventory_hostname}}"
          loop: "{{ groups['web'] }}"

Step 5

Next, add the second task for bigip_pool as demonstrated in Exercise 1.3 - Adding a load balancing pool.

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

  tasks:
    - name: Setup provider
      set_fact:
        provider:
          server: "{{private_ip}}"
          user: "{{ansible_user}}"
          password: "{{ansible_password}}"
          server_port: "8443"
          validate_certs: "no"

    - name: SETUP AND GRACEFUL ROLLBACK BIG-IP CONFIGURATION
      block:
        - name: CREATE NODES
          f5networks.f5_modules.bigip_node:
            provider: "{{provider}}"
            host: "{{hostvars[item].ansible_host}}"
            name: "{{hostvars[item].inventory_hostname}}"
          loop: "{{ groups['web'] }}"

        - name: CREATE POOL
          f5networks.f5_modules.bigip_pool:
            provider: "{{provider}}"
            name: "http_pool"
            lb_method: "round-robin"
            monitors: "/Common/http"
            monitor_type: "and_list"

Step 6

Next, add the third task. For the third task use the bigip_pool_member as demonstrated in Exercise 1.4 - Adding members to a pool.

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

  tasks:
    - name: Setup provider
      set_fact:
        provider:
          server: "{{private_ip}}"
          user: "{{ansible_user}}"
          password: "{{ansible_password}}"
          server_port: "8443"
          validate_certs: "no"

    - name: SETUP AND GRACEFUL ROLLBACK BIG-IP CONFIGURATION
      block:
        - name: CREATE NODES
          f5networks.f5_modules.bigip_node:
            provider: "{{provider}}"
            host: "{{hostvars[item].ansible_host}}"
            name: "{{hostvars[item].inventory_hostname}}"
          loop: "{{ groups['web'] }}"

        - name: CREATE POOL
          f5networks.f5_modules.bigip_pool:
            provider: "{{provider}}"
            name: "http_pool"
            lb_method: "round-robin"
            monitors: "/Common/http"
            monitor_type: "and_list"

        - name: ADD POOL MEMBERS
          f5networks.f5_modules.bigip_pool_member:
            provider: "{{provider}}"
            state: "present"
            name: "{{hostvars[item].inventory_hostname}}"
            host: "{{hostvars[item].ansible_host}}"
            port: "80"
            pool: "http_pool"
          loop: "{{ groups['web'] }}"

Step 7

Next, add the fourth task. For the fourth task use the bigip_virtual_server as demonstrated in Exercise 1.5 - Adding a virtual server.

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

  tasks:
    - name: Setup provider
      set_fact:
        provider:
          server: "{{private_ip}}"
          user: "{{ansible_user}}"
          password: "{{ansible_password}}"
          server_port: "8443"
          validate_certs: "no"

    - name: SETUP AND GRACEFUL ROLLBACK BIG-IP CONFIGURATION
      block:
        - name: CREATE NODES
          f5networks.f5_modules.bigip_node:
            provider: "{{provider}}"
            host: "{{hostvars[item].ansible_host}}"
            name: "{{hostvars[item].inventory_hostname}}"
          loop: "{{ groups['web'] }}"

        - name: CREATE POOL
          f5networks.f5_modules.bigip_pool:
            provider: "{{provider}}"
            name: "http_pool"
            lb_method: "round-robin"
            monitors: "/Common/http"
            monitor_type: "and_list"

        - name: ADD POOL MEMBERS
          f5networks.f5_modules.bigip_pool_member:
            provider: "{{provider}}"
            state: "present"
            name: "{{hostvars[item].inventory_hostname}}"
            host: "{{hostvars[item].ansible_host}}"
            port: "80"
            pool: "http_pool"
          loop: "{{ groups['web'] }}"

        - name: ADD VIRTUAL SERVER
          f5networks.f5_modules.bigip_virtual_server:
            provider: "{{provider}}"
            name: "vip"
            destination: "{{private_ip}}"
            port: "443"
            enabled_vlans: "all"
            all_profiles: ['http', 'clientssl', 'oneconnect']
            pool: "http_pool"
            snat: "Automap1"

Step 7

Next, add the rescue stanza. The tasks under the rescue stanza will be identical to Exercise 2.1 - Deleting F5 BIG-IP Configuration. The bigip_pool_member task does not need to re-enterered since by deleting the nodes and pool will remove all configuration. If any task within the block fails, the rescue stanza will execute in order. The VIP, pool, and nodes will be removed gracefully.

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

  tasks:
    - name: Setup provider
      set_fact:
        provider:
          server: "{{private_ip}}"
          user: "{{ansible_user}}"
          password: "{{ansible_password}}"
          server_port: "8443"
          validate_certs: "no"

    - name: SETUP AND GRACEFUL ROLLBACK BIG-IP CONFIGURATION
      block:
        - name: CREATE NODES
          f5networks.f5_modules.bigip_node:
            provider: "{{provider}}"
            host: "{{hostvars[item].ansible_host}}"
            name: "{{hostvars[item].inventory_hostname}}"
          loop: "{{ groups['web'] }}"

        - name: CREATE POOL
          f5networks.f5_modules.bigip_pool:
            provider: "{{provider}}"
            name: "http_pool"
            lb_method: "round-robin"
            monitors: "/Common/http"
            monitor_type: "and_list"

        - name: ADD POOL MEMBERS
          f5networks.f5_modules.bigip_pool_member:
            provider: "{{provider}}"
            state: "present"
            name: "{{hostvars[item].inventory_hostname}}"
            host: "{{hostvars[item].ansible_host}}"
            port: "80"
            pool: "http_pool"
          loop: "{{ groups['web'] }}"

        - name: ADD VIRTUAL SERVER
          f5networks.f5_modules.bigip_virtual_server:
            provider: "{{provider}}"
            name: "vip"
            destination: "{{private_ip}}"
            port: "443"
            enabled_vlans: "all"
            all_profiles: ['http', 'clientssl', 'oneconnect']
            pool: "http_pool"
            snat: "Automap1"

      rescue:
        - name: DELETE VIRTUAL SERVER
          f5networks.f5_modules.bigip_virtual_server:
            provider: "{{provider}}"
            name: "vip"
            state: absent

        - name: DELETE POOL
          f5networks.f5_modules.bigip_pool:
            provider: "{{provider}}"
            name: "http_pool"
            state: absent

        - name: DELETE NODES
          f5networks.f5_modules.bigip_node:
            provider: "{{provider}}"
            name: "{{hostvars[item].inventory_hostname}}"
            state: absent
          loop: "{{ groups['web'] }}"

Step 8

Finally add the always to save the running configuration.

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

  tasks:
    - name: Setup provider
      set_fact:
        provider:
          server: "{{private_ip}}"
          user: "{{ansible_user}}"
          password: "{{ansible_password}}"
          server_port: "8443"
          validate_certs: "no"

    - name: SETUP AND GRACEFUL ROLLBACK BIG-IP CONFIGURATION
      block:
        - name: CREATE NODES
          f5networks.f5_modules.bigip_node:
            provider: "{{provider}}"
            host: "{{hostvars[item].ansible_host}}"
            name: "{{hostvars[item].inventory_hostname}}"
          loop: "{{ groups['web'] }}"

        - name: CREATE POOL
          f5networks.f5_modules.bigip_pool:
            provider: "{{provider}}"
            name: "http_pool"
            lb_method: "round-robin"
            monitors: "/Common/http"
            monitor_type: "and_list"

        - name: ADD POOL MEMBERS
          f5networks.f5_modules.bigip_pool_member:
            provider: "{{provider}}"
            state: "present"
            name: "{{hostvars[item].inventory_hostname}}"
            host: "{{hostvars[item].ansible_host}}"
            port: "80"
            pool: "http_pool"
          loop: "{{ groups['web'] }}"

        - name: ADD VIRTUAL SERVER
          f5networks.f5_modules.bigip_virtual_server:
            provider: "{{provider}}"
            name: "vip"
            destination: "{{private_ip}}"
            port: "443"
            enabled_vlans: "all"
            all_profiles: ['http', 'clientssl', 'oneconnect']
            pool: "http_pool"
            snat: "Automap1"

      rescue:
        - name: DELETE VIRTUAL SERVER
          f5networks.f5_modules.bigip_virtual_server:
            provider: "{{provider}}"
            name: "vip"
            state: absent

        - name: DELETE POOL
          f5networks.f5_modules.bigip_pool:
            provider: "{{provider}}"
            name: "http_pool"
            state: absent

        - name: DELETE NODES
          f5networks.f5_modules.bigip_node:
            provider: "{{provider}}"
            name: "{{hostvars[item].inventory_hostname}}"
            state: absent
          loop: "{{ groups['web'] }}"

      always:
        - name: SAVE RUNNING CONFIGURATION
          f5networks.f5_modules.bigip_config:
            provider: "{{provider}}"
            save: true

The above playbook will try and configure the Virtual Server, Pool and Nodes but since the snat value is provided as ‘Automap1’ the addition of virtual server will fail and the ‘rescue’ block will be run.

Save File and exit out of editor.

Step 9

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

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

Playbook Output

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

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

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

TASK [CREATE NODES] ***********************************************************
changed: [f5] => (item=node1)
changed: [f5] => (item=node2)

TASK [CREATE POOL] ************************************************************
changed: [f5]

TASK [ADD POOL MEMBERS] *******************************************************
changed: [f5] => (item=node1)
changed: [f5] => (item=node2)

TASK [ADD VIRTUAL SERVER] ****************************************************
fatal: [f5]: FAILED! => changed=false
  msg: '0107163f:3: Pool (/Common/Automap1) of type (snatpool) doesn''t exist.'

TASK [DELETE VIRTUAL SERVER] **************************************************
ok: [f5]

TASK [DELETE POOL] ************************************************************
changed: [f5]

TASK [DELETE NODES] ***********************************************************
changed: [f5] => (item=node1)
changed: [f5] => (item=node2)

TASK [SAVE RUNNING CONFIGURATION] *********************************************
changed: [f5]

PLAY RECAP ********************************************************************
f5                         : ok=8    changed=6    unreachable=0    failed=0
skipped=0    rescued=1    ignored=0

Solution

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

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