What are the benefits and risks of canary deployment compared to blue green deployment?

1 Blue Green Deployment

Blue green deployment involves having two identical environments: one blue and one green. The blue environment is the current production version, while the green environment is the new version that is ready to be deployed. When the green environment is fully tested and verified, the traffic is switched from the blue to the green, making the green the new production version. The blue environment is kept as a backup in case of any issues or rollback needs. This method ensures a fast and smooth transition, as there is no downtime or partial deployment.

3 Benefits of Canary Deployment

Canary deployment has several benefits over blue green deployment, especially for large and complex systems. First, it reduces the risk of introducing a major bug or error that affects all users or servers, as only a small portion of them are exposed to the new version. Second, it allows for more accurate and real-time feedback from the users or servers that receive the new version, as they can compare it to the old version and report any issues or improvements. Third, it enables more flexibility and experimentation, as the developers can try out different features or configurations on different segments of users or servers, and measure their impact.

4 Risks of Canary Deployment

Canary deployment also has some risks and challenges that need to be considered before choosing this method. First, it requires more resources and coordination, as the developers need to maintain and manage multiple versions of the system at the same time, and ensure that they are compatible and consistent. Second, it can create a fragmented and inconsistent user experience, as some users or servers may have access to different features or functionalities than others, and may encounter different bugs or errors. Third, it can take longer and be more complex to complete the deployment, as the developers need to monitor and analyze the results of each increment, and decide when and how to proceed to the next one.

5 When to Use Blue Green or Canary Deployment

The choice between blue green deployment and canary deployment depends on several factors, such as the size and complexity of the system, the frequency and scope of the updates, the availability and reliability of the testing and monitoring tools, and the expectations and preferences of the users or customers. In general, blue green deployment is more suitable for small and simple systems, or for updates that are infrequent and minor, as it offers a faster and simpler way to deploy the new version. Canary deployment is more suitable for large and complex systems, or for updates that are frequent and major, as it offers a safer and more flexible way to test and release the new version.