Overview
This lecture introduces Ansible for server automation and demonstrates how to orchestrate Ansible tasks at scale using Kestra, a modern workflow automation tool.
Introduction to Ansible
- Ansible is an automation tool for installing software, managing configs, and updating systems.
- It operates agentlessly, requiring only SSH access and Python on target machines.
- Tasks are described in YAML “playbooks,” which can be executed across multiple servers at once.
- Playbooks can handle tasks like package installation, gathering system info, or automating audits.
Real-World Ansible Example
- Example playbook collects system details like OS, memory, CPU, open ports, and installed applications.
- Useful for system audits, troubleshooting, and inventory tracking.
- Playbooks simplify operations on large server fleets, replacing manual commands.
Infrastructure Automation and Orchestration
- Infrastructure automation turns repetitive infra tasks (e.g., VM provisioning, config management) into code.
- Tools like Terraform, Docker, and Ansible are often used together in DevOps.
- Workflow orchestration coordinates tasks, dependencies, retries, and error handling across tools.
Introduction to Kestra
- Kestra is an open-source orchestration engine for chaining infra tasks into unified, version-controlled workflows (flows).
- Flows are defined declaratively in YAML and support versioning, scheduling, and external triggers (e.g., Git events).
- Supports secrets, variable passing, error handling, logging, and scaling.
- Integrates with tools like Ansible, Terraform, Docker, and works on any cloud or on-premises.
Running Ansible Playbooks with Kestra
- Kestra uses plugins (e.g., Ansible CLI) to run playbooks in isolated containers.
- Files such as inventory.ini and playbooks can be uploaded or added inline in flows.
- Tasks are specified in flows, supporting both simple and complex automation scenarios.
- Outputs, logs, and artifacts from runs are accessible directly within Kestra.
Advanced Kestra Automation Features
- Namespace files enable organizing and running entire infra projects by grouping related files and flows.
- Supports drag-and-drop UI and blueprints for reusable automation patterns.
- Triggers allow scheduling flows or responding to events (e.g., commits, webhooks, API calls).
- Output files from flow executions are downloadable for further use.
Key Terms & Definitions
- Ansible — Agentless automation tool for system management tasks.
- Playbook — YAML file defining a set of tasks for Ansible to execute.
- Kestra — Open-source workflow orchestration engine for automating and connecting infra tasks.
- Flow — Kestra’s term for a sequence of automated tasks described in YAML.
- Namespace — Logical grouping of flows and resources in Kestra.
Action Items / Next Steps
- Explore the Kestra GitHub repository and try sample flows.
- Test creating and executing Ansible playbooks both standalone and via Kestra.
- Experiment with organizing project files using Kestra namespaces.
- Check Kestra’s documentation for advanced triggers and plugin examples.
- Prepare for the upcoming Kestra Hack Week by building and running custom flows.