Ansible Scenario based interview question & Answers

 

1. You deployed an Ansible playbook, but it fails on some hosts while working on others. How would you debug and resolve this?

Steps to debug:

• Use ansible-playbook -vvv playbook.yml to enable verbose mode for more detailed logs.
• Check the error message and failed task details.
• Run ansible all -m ping to verify host connectivity.
• Use ansible all -m setup to check system facts and detect OS/config differences.
• Verify inventory configuration and ensure host groups are correctly assigned.
• Run affected tasks in isolation using --limit <hostname> and --step to execute interactively.

Resolution:

• If the issue is environment-specific, modify the playbook to handle different OS versions or missing dependencies using when conditions.
• Fix missing permissions by using become: yes where required.

---

2. Your Ansible playbook takes too long to execute. How would you optimize it for faster performance?

Optimization techniques:

• Use serial in playbooks to run tasks in parallel instead of executing sequentially.
• Use fact caching (fact_caching: jsonfile) to avoid gathering facts repeatedly.
• Use async & poll for long-running tasks to execute asynchronously.
• Reduce SSH overhead by setting pipelining = True in ansible.cfg.
• Optimize loops by using with_items instead of separate tasks.
• Use changed_when and check_mode to avoid unnecessary task execution.

---

3. You need to ensure that Ansible applies configurations only if there’s a change. How would you implement this?

• Use idempotent modules like copy, template, lineinfile, and file, which apply changes only when required.
• Use changed_when in shell/command tasks to detect actual changes.
• Use notify handlers to trigger actions only when a task reports a change.
• Use check_mode: yes to dry-run and see changes before applying them.

---

4. After an Ansible update, your playbooks start failing due to deprecated modules. How do you handle this situation?

Steps to resolve:

• Identify deprecated modules by running ansible-playbook --check -vvv playbook.yml.
• Check the Ansible release notes for alternative modules.
• Modify playbooks to use recommended replacements (e.g., replacing ec2 with amazon.aws.ec2_instance).
• Test the updated playbook in a non-production environment before deploying.
• Pin the working Ansible version using pip install ansible==<working-version> if immediate migration isn’t possible.

---

5. Your Ansible playbook is executing but not making the expected changes to remote servers. How would you troubleshoot?

• Run the playbook with --check --diff to preview changes before applying.
• Check register variables to validate task outputs.
• Ensure the changed_when condition is correctly set.
• Verify correct become privileges are applied.
• Check inventory and variables using ansible-inventory --graph.
• Review logs using -vvv for deeper insights.

---

6. How would you design an Ansible architecture to scale across multiple regions with minimal overhead?

Key considerations:

• Use Ansible Tower/AWX to centralize execution and manage multiple environments.
• Implement a dynamic inventory for cloud-based scaling (AWS, Azure, GCP).
• Use delegate_to and local_action to reduce SSH connections.
• Leverage pull-based execution using ansible-pull for distributed control.
• Use fact caching and log aggregation for efficient execution.
• Optimize networking by using regional jump hosts or bastion servers.

---

7. You need to ensure zero downtime while applying Ansible playbooks in production. What approach would you take?

• Use rolling updates with serial: <N> to update a few hosts at a time.
• Implement blue-green deployment by switching traffic between two environments.
• Use canary deployment, applying changes to a subset before full rollout.
• Ensure health checks before restarting critical services.
• Use reboot module with pre/post checks to prevent downtime.

---

8. An Ansible playbook is stuck waiting for user input, causing automation failures. How would you fix it?

• Check for tasks requiring interactive input and set -e "ansible_ask_pass=False".
• Use no_log: true for sensitive prompts (passwords, secrets).
• Pass required values via extra_vars (-e "var_name=value").
• Modify prompts in playbook with default values to avoid manual input.

---

9. Your Ansible deployment in a hybrid cloud environment is failing due to network latency. What strategies can you use?

• Use multiple inventory sources for better region-based execution.
• Implement Ansible Tower/AWX to manage execution closer to target regions.
• Reduce SSH connections by batching tasks with serial and forks.
• Use ansible-pull for edge deployments to reduce network overhead.
• Optimize playbook logic to minimize repeated connections.

---

10. You need to apply a security patch across 1,000+ servers using Ansible while ensuring rollback in case of failure. How would you do this?

Steps for safe deployment:

1. Take a backup before applying changes using the fetch or copy module.
2. Deploy in batches using serial: <N> to minimize impact.
3. Verify patch installation using a test_command before moving forward.
4. Rollback strategy:
   • Use when conditions to apply rollback if verification fails.
   • Store a snapshot of critical files (tar backup).
   • Revert to previous packages if necessary (yum history undo or dpkg --remove).
5. Monitor & alert: Use notify handlers to report failures immediately.

Essential HTTP Status Codes

 

DevOps Vs SRE vs Platform Engineering