Topic - Rolling deployment

Introduction

 

Rolling deployment is a deployment strategy that is used to update software applications without causing any downtime. This is achieved by deploying the new version of the application in small batches across multiple instances, while keeping the old version running until the new version is fully deployed. This article will provide a detailed overview of the rolling deployment model, its benefits and drawbacks, and how it can be implemented.

 

What is Rolling Deployment?

 

Rolling deployment is a deployment strategy that involves deploying new software updates in a controlled and incremental manner. The idea behind this approach is to minimize downtime and ensure that the application remains available to users during the deployment process.

 

The rolling deployment process typically involves deploying the new version of the software to a small subset of the application's instances, testing the new version to ensure it is working as expected, and then gradually deploying the new version to more instances.

 

Benefits of Rolling Deployment

 

One of the main benefits of rolling deployment is that it minimizes downtime during the deployment process. By deploying the new version in small batches, the application remains available to users throughout the deployment process.

 

Another benefit of rolling deployment is that it allows for easy rollback in case of issues. Since the new version is deployed in small batches, it is easier to identify any issues and roll back to the previous version if necessary.

 

Rolling deployment also allows for better system resiliency. By deploying the new version in small batches, the impact of any issues is limited to a small subset of the application's instances, minimizing the impact on the overall system.

 

Drawbacks of Rolling Deployment

 

One of the main drawbacks of rolling deployment is that it can be complex and time-consuming to set up. Rolling deployment requires careful planning and coordination to ensure that the new version is deployed in a controlled and incremental manner.

 

Another potential drawback of rolling deployment is that it can be resource-intensive. Since the new version is deployed in small batches, multiple instances of the application may need to be provisioned, which can be expensive.

 

Implementing Rolling Deployment

 

Implementing rolling deployment requires careful planning and coordination. Here are some key steps to follow when implementing rolling deployment:

 

Define the deployment plan: Before starting the deployment process, it is important to define a deployment plan that outlines the steps involved in the deployment process.

 

Deploy the new version to a small subset of instances: Start by deploying the new version of the software to a small subset of the application's instances.

 

Test the new version: Once the new version has been deployed to a small subset of instances, test the new version to ensure that it is working as expected.

 

Gradually deploy the new version to more instances: If the new version is working as expected, gradually deploy the new version to more instances. If any issues are identified during the deployment process, roll back to the previous version and investigate the issue.

 

Conclusion

 

Rolling deployment is a deployment strategy that allows for the seamless deployment of new software updates without causing downtime. By deploying the new version in small batches, rolling deployment minimizes downtime and allows for easy rollback in case of issues. However, rolling deployment can be complex and time-consuming to set up, requiring careful planning and coordination. Overall, rolling deployment is a powerful tool that can help ensure the availability and reliability of software applications.