Container Service provides two release strategies: blue-green release and standard release. These two release strategies differ in:
|Standard release||Delete the earlier version when deploying the new version of application. Your service will be temporarily interrupted in the process of release.|
|Blue-green release||Blue version and green version are generated when the application is updated. These two versions play an active-standby role to each other and go online or offline based on your configured route weight.
This kind of release strategy has the following features:
- The service is not interrupted.
- The application never goes down.
- Users do not realize the restart in the process of release.
- The application automatically rolls back if the update fails.
- Multiple updates and iterations can be performed on the same resource stack.
Note: Applications created by using images cannot be updated using blue-green release strategy.
The standard release, a traditional release strategy for applications, deploys the new version of the application in the current environment. This release strategy is generally used except for special needs. The usage scenarios include:
- The new version has been fully tested, with no need of online test run.
- The application includes database service and has been updated in an unreversible manner, such as datasheet structure change. In this scenario, standard release avoids business transformation, such as data migration and rollback.
Application forms that are applicable to blue-green release include the frontend services and backend services. Blue-green release is often used in the incremental update of applications. The specific customer-facing business scenarios that use this kind of release strategy include:
Guarantee of the business continuity
The frequent iterations of application versions is a real challenge to Internet enterprises with quickly-changing business. It is necessary to ensure the continuity of online business. The main value of blue-green release strategy is to achieve application update with no downtime, ensure the service is not interrupted, and meet the requirements of sustainable release of updated applications in the cloud environment.
Online evaluation of new version
Blue-green release strategy enables you to perform the version test in the online environment, and fully test the service functions, performance, and security of the new version by keeping the earlier and the latest versions coexisting for a period of time. When the new version is stable, bring the earlier version offline.