ChatGPT AI: kubernetes blue-green deployment

this is non-trivial question;
ChatGPT answers are surprisingly close, while a not very specific
promising tech! 
Google search is still more useful for cases like this, though :)

https://chat.openai.com/chat 

prompt: "explain kubernetes blue-green deployment"

answer: 

"Blue-green deployment is a technique used to deploy new versions of software with minimal downtime. It involves creating two identical environments, called "blue" and "green", which are used to deploy the software. The "blue" environment is the production environment where the software is currently running, while the "green" environment is used to test the new version of the software before it is released.

To perform a blue-green deployment, the new version of the software is first deployed to the "green" environment. The application is then tested in the green environment to ensure that it is functioning correctly. Once the testing is complete, the application is switched to the "blue" environment, and the old version is shut down. This allows for a seamless transition to the new version, as the application is always available to users during the deployment process.

Kubernetes, a container orchestration platform, can be used to automate the blue-green deployment process. Kubernetes provides tools and features that make it easy to deploy and manage containerized applications, including rolling updates and rollbacks, which can be used to perform blue-green deployments.

Using Kubernetes, you can define a deployment configuration that specifies the number of replicas of your application that should be running at any given time. When you want to perform a blue-green deployment, you can create a new deployment configuration that points to the new version of your application, and then use Kubernetes to update the deployment to use the new version. This allows you to easily switch between the blue and green environments and ensure that the new version of the application is fully tested before it is deployed to production."

prompt: "example of kubernetes blue-green deployment"

answer:

"Blue-green deployment is a technique used to minimize downtime during deployments by allowing the new version of the application to be tested in parallel with the existing version. This can be achieved using Kubernetes by creating two separate environments, referred to as the "blue" and "green" environments.

Here is an example of how blue-green deployment can be implemented using Kubernetes:

1. Create two separate environments in Kubernetes, one for the "blue" version of the application and one for the "green" version.
2. Deploy the new "green" version of the application to the green environment and test it to ensure it is working correctly.
3. Once the green version has been tested and is deemed ready for production, switch the traffic from the blue environment to the green environment by updating the service's load balancer to point to the green pods.
4. After the traffic has been successfully switched to the green environment, delete the blue environment.

This process allows for minimal downtime during deployments, as the new version of the application is tested in parallel with the existing version and traffic is only switched once the new version has been tested and is deemed ready for production.

here is from official documentation:
Zero-downtime Deployment in Kubernetes with Jenkins | Kubernetes