Canary deployment

The term “canary” is derived from the use of canaries in coal mines as an early warning system for detecting toxic gases. Similarly, canary deployments act as early warning systems to detect potential issues before they affect the wider audience. Canary deployments are commonly used in conjunction with automation and continuous delivery practices, allowing teams to release changes more frequently and confidently. By reducing the blast radius of potential issues, canary deployments promote a culture of continuous improvement and reliability in software development and operations. Canary deployment is very important if you want to roll out new features or updates to a small number of users or servers before making the changes available to the entire user base or infrastructure.

Important components in canary deployment

• Version Deployment:
  A new version of the software or application is prepared and ready for release.
• Small Initial Release:
  Initially, the new version is deployed to a small number of users or servers, often chosen randomly or based on the basis of geographic location or user behavior. This small group acts as the “canary group”
• Monitoring and Observing:
  During canary deployment, monitoring and observability tools are used to collect data and metrics about the performance and behavior of the new version.
  This includes measuring response times, error rates, resource usage, and any other relevant indicators. These metrics help in identifying potention issues
• Gradual Expansion and Rollback:
  If the canary group shows positive results and stable performance, the deployment can be expanded to a larger audience or servers. Conversely, if issues are detected, the deployment can be stopped or rolled back.

Canary deployments are commonly used in various types of software, including:

1. Web Applications:
   Canary deployments are frequently employed for web applications to test new features, bug fixes, or performance improvements before pushing changes to the entire user base.
2. Mobile Applications:
   Mobile app developers can use canary deployments to release new app versions to a small percentage of users or devices to gather feedback and identify potential problems before a full release.
3. Microservices:
   In a microservices architecture, canary deployments can be used to gradually update individual services without disrupting the entire system.
4. Cloud Infrastructure:
   Canary deployments are useful for testing changes to cloud infrastructure configurations or services before applying them globally.
5. Internet of Things (IoT) Devices:
   Manufacturers of IoT devices may use canary deployments to release firmware updates to a subset of devices first to ensure stability and avoid widespread issues.
6. APIs and Backend Services:
   Canary deployments can be used to test updates to APIs and backend services with a controlled rollout to avoid service disruptions.
7. Desktop Applications:
   Software companies that develop desktop applications can utilize canary deployments to test new versions on a limited number of users or specific regions.