The use of blue–green deployments provides us with the following set of benefits:
- The ability to switch the application from one version to another instantly
- The ability to easily roll back the application from a newer version to an older version in case the new version experiences some critical functionality bugs
- A reduction in downtime related to application upgrades
Using a canary deployment can help in the testing of an application in the following ways:
- The application is tested with a small sample of real-world requests, which may help expose any unidentified bugs in the application
- Canary deployment gives us the ability to run the new version of the application along with the older version so as to compare the responses provided by the APIs
Using virtual machines for running microservices-based applications can cause increased overhead for running the microservice instances because of the higher requirements incurred by a virtual machine. In addition, the use of virtual machines limits the number of services that can coexist on the same infrastructure because a virtual machine is comparably heavier to run than containers, which utilize operating-system functionality to keep the programs isolated.
The deployments in the hybrid cloud model can be handled in the same way that they are handled in the public or private clouds. The difference arises when the application needs to be scaled. In this case, when using the hybrid cloud approach, an organization can pool the resources from the public cloud based on the scaling necessity and can then run some parts of their application in the public cloud and the others in the private cloud.