Exercise 4.3: Creating Node Maintenance Workflow

Objective

Demonstrate another use case of Ansible Automation Controller workflow for F5 BIG-IP.

For this exercise, we will create a workflow for server patch management, first to disable the pool members, patch the nodes, and then enable the nodes. In parallel, we also attach an iRule to virtual server, to respond to the users when servers are under maintenance.

Guide

Step 1: Prepare Job Templates

Note

If you havent run the section 4.2 Step 11 (Please do this prior to moving forward)

Similar to the previous lab, we need to create the following templates by following Lab 4.2:

NAME	Playbook
Disable node	disable_node.yml
Enable node	enable_node.yml
Patch server	patch_server.yml
Attach iRule	attach_irule.yml
Detach iRule	detach_irule.yml

Again, we use the same template parameters as Lab 4.2 for each of the above templates, except for Patch server. This template will use credential Workshop Credential, and all other templates will be using BIGIP

Parameter	Value
NAME
JOB TYPE	Run
INVENTORY	Workshop Inventory
PROJECT	Workshop Project
PLAYBOOK
CREDENTIALS

Here is one example templates configured:

Step 2: Create a Workflow Template

1. Click on the Templates link on the left menu.

2. Click on the button. Select the Workflow Template.

3. Fill out the form as follows:

   Parameter	Value
   NAME	Node maintenance workflow
   ORGANIZATION	Default
   INVENTORY	Workshop Inventory

   

4. Click on the Save button

Step 3: The Workflow Visualizer

1. When you click the SAVE button, the WORKFLOW VISUALIZER should automatically open. If not click on the blue WORKFLOW VISUALIZER button.

2. By default only a green START button will appear. Click on the START button.

3. The ADD A NODE window will appear on the right.

Step 4: Disable node Template

1. Select the Disable node Job Template. Use the drop down box to select run. Select Always from left navigator menu option called Run type.

2. Click the Save button.

   

Step 5: Attach iRule Template

1. Click on the START button, again. The ADD A NODE will appear again.

2. Select the Attach iRule job template. Select Always from left navigator menu option called Run type.

3. Click the Save button.

   

Step 6: Patch server Template

1. Hover over the Disable node node and click the + symbol. The ADD A NODE will appear again.

2. Select the Patch server job template. Select On Success from left navigator menu option called Run type.

3. Click the Save button.

   

Step 7: Enable node Template

1. Hover over the Patch server node and click the + symbol. The ADD A NODE will appear again.

2. Select the Enable node job template. Select On Success from left navigator menu option called Run type.

3. Click the Save button.

   

Step 8: Detach iRule Template

1. Hover over the Enable node node and click the + symbol. The ADD A NODE will appear again.

2. Select the Detach iRule job template. Select On Success from left navigator menu option called Run type.

3. Click the Save button.

   

Step 9: Create a converged link

Lastly, we create a convergence link, which allows the jobs running in parallel to converge. In another word, when both jobs finish, Detach iRule node will trigger.

1. Hover over the Attach iRule to virtual server node and click the chain symbol.

2. Now, click on the existing Detach iRule. An ADD LINK window will appear. For the RUN parameter choose Always.

   

3. Click the SAVE button again to save the workflow.

Step 10: Run the Workflow

1. Return to the Templates window

2. Click the launch button to launch the Node maintenance workflow template.

   

   At any time during the workflow job you can select an individual job template by clicking on the node to see the status.

3. With the iRule attached to virtual server, users will receive a maintenance page during the server maintenance:

   

Verifying the web servers

• Each RHEL web server actually already has a webserver running. Exercise 1.1 through 1.5 have successfully setup the load balancer for the pool of web servers. To view the results of the Web services:

  • In the UDF Console goto the External Client and select Access and then select FireFox

  • In the Bookmarks bar you can select the Ansible Labs Folder and goto 101 - Labs and Select HTTPS

  • OR within the browser you can browse to https://10.1.20.30/

  • You will need to bypass the certificate warning (within Firefox Warning –> Advanced –> Accept the Risk and Continue)

Takeaways

You have

• Created a workflow template that disables pool members, upgrade web servers, and add servers back to the pool

• Attached iRule to virtual server, and user will get maintenance page during server patch

• Launched the workflow template and explored the VISUALIZER

Complete

You have completed lab exercise 4.3

Click here to return to the Ansible Network Automation Workshop