Introduction
Azure mission-critical design methodology requires continuous validation to make sure your workload stays operational, even when failures and unexpected situations happen. It involves testing changes and releases regularly in a controlled environment. Such tests can include sustained user load and injecting faults. The goal is to test the workload's resiliency and its ability to handle faults before deploying to production.
Continuous validation is implemented as a set of processes and tools. It should be integrated into a workflow to enable developers and operations teams to run the validation consistently and regularly, for instance before every release or major code change. The validation processes should be run under production-like conditions.
Here are the high-level tasks for designing continuous validation:
- Define tests based on user and system flows, and their expected performance.
- Establish baselines for various scenarios and stages.
- Evaluate and adjust baselines and thresholds regularly.
- Implement Azure services in automated pipelines.
Microsoft Azure provides these services to implement load testing and chaos engineering:
- Azure Load Testing is a managed service for generating synthetic, real-world traffic to test the application and underlying infrastructure and services.
- Azure Chaos Studio is a managed service that provides chaos engineering capabilities to systematically inject failures into key components of the application.
You can run the two services simultaneously by embedding them in an Azure DevOps continuous integration and continuous delivery (CI/CD) pipeline. You'll be able to validate the impact of application changes under realistic conditions at any time in the development cycle.
Example scenario
This module incorporates continuous validation to an example introduced as part of the learning path. We recommend that you familiarize yourself with that example, especially these aspects.