Anton Alputov BLUE/GREEN DEPLOYMENT
Good day, dear colleagues. Today, I am pleased to present a report on the topic of Blue/Green Deployment. This deployment method is becoming increasingly popular due to its advantages and its ability to minimize risks when releasing new application versions. Today, we will explore the principles behind this method, its benefits, and real-world use cases, including my experience with migrating production and development environments in AWS with seamless data replication. Our goal is to demonstrate how Blue/Green Deployment can help you improve the deployment process, making it more secure and reliable. Let's get started!
LOAD BALANCE
USERS
Let's take a closer look at how Blue/Green Deployment works. The core principle is to divide the infrastructure into two identical environments: Blue and Green. Blue is the current production environment that handles all user requests, while Green is the environment where we deploy the new version of our application. The process begins by deploying the new version of the application in the Green environment. It's important to note that the Green environment is identical to Blue, except for the version of the application. This allows us to conduct all necessary testing and ensure that the new version functions correctly.
After successful testing, we begin the process of switching traffic from the Blue environment to the Green environment. This can be done in various ways, such as modifying DNS settings or using a load balancer. As a result, the Green environment becomes the new production environment, while the Blue environment serves as a backup.
One of the key advantages of Blue/Green Deployment is the minimization of downtime. The switch happens almost instantly, and users are unaware of the update process. This method also allows for easy rollback to the previous version.
If any issues arise with the new version, we simply redirect the traffic back to the Blue environment.
Now, let's look at the specific advantages that Blue/Green Deployment offers. This deployment method provides several key benefits that make it appealing to many organizations:
1. Minimized downtime.
2. Easy rollback.
3. A/B testing support.
4. Shorter MTTR time.
1. Minimized downtime
Firstly, minimizing downtime risk. Since we always have a backup environment to revert to in case any issues arise, we significantly reduce the risk associated with releasing new versions. This is especially important for mission-critical applications, where even a small failure can lead to serious consequences.
issues, we can quickly and easily redirect traffic back to the previous version, ensuring minimal downtime for users.
This swift transition helps maintain service availability and reduces the impact of potential errors.
3. A/B testing support
The third advantage is the ability to conduct A/B testing. Since we have two identical environments, we can route a portion of the traffic to the new version and assess its performance and stability in real-world conditions before fully switching over. This allows for data-driven decisions and reduces the risk of unforeseen issues when deploying the new version to all users.
4. Shorter MTTR time
Lastly, Blue/Green Deployment significantly improves recovery time in the event of incidents. Since the backup environment is always ready for use, we can quickly restore the application's functionality.
As you can see, this deployment method offers numerous benefits that make the deployment process safer and more reliable.
Migration to AWS AWS CDK v2
Now, let's move on to a real-world example of Blue/Green Deployment from my own experience. Recently, we had to migrate AWS CDK to its second version, as well as move both production and development environments in AWS from one account to other accounts. This process involved a significant update to the entire codebase and architecture. Due to the monorepo structure, it was difficult to migrate service by service, and this migration included deploying all necessary services on the new accounts, replicating data, and seamlessly switching traffic.
Migration to AWS AWS CDK v2
I started by preparing the Green environment on the new AWS account. This involved deploying all the necessary services, such as the database, Kafka, ECS clusters, networking components, and other AWS services. I also set up synchronization of S3 buckets, database replication, and mirroring of Kafka brokers between the old (Blue) and new (Green) environments to ensure data consistency at the moment of the switch.
Once the Green environment was fully ready and tested, we began the process of switching the traffic.
Migration to AWS AWS CDK v2
We used Route 53 to modify the NS records, which allowed us to redirect all user requests from the Blue environment to the Green environment almost instantly, minimizing downtime. I applied this approach for each environment, migrating them to separate accounts.
As a result, the migration was seamless, with no noticeable interruption in service for users. This allowed us to successfully update the infrastructure and move to new AWS accounts without any negative impact. This example clearly demonstrates how Blue/Green Deployment can be effectively used for safe and efficient migration between accounts.
Blue/Green Deployment implementation using various AWS services
In Amazon ECS, you can easily set up two identical task groups: one representing the Blue environment and the other the Green. After deploying a new version in the Green environment, traffic can be switched using a load balancer.
In this case, we use the same load balancer but with two listener rules that listen on different ports: 8080 for Blue and 80 for Green.
The deployment completes by switching listener rules between the two target groups, ensuring a quick and safe transition to the new version. If issues arise, it's easy to revert back to the previous version by reassigning traffic.
2. AWS Elastic Beanstalk:
Elastic Beanstalk has built-in Blue/Green Deployment support. You can deploy a new version of your application in the Green environment, test it, and then switch traffic using the "Swap environment URLs" feature.
This simply swaps the CNAME records of the old and new environments, effectively redirecting traffic from the old version to the new one. This approach is similar to the account migration example I shared earlier.
3. AWS Lambda with Application Load Balancer and Weighted Target Groups:
In this scenario, you create two versions of a Lambda function: Blue and Green. Each function version is tied to a separate target group in an Application Load Balancer (ALB).
You can gradually shift traffic from the Blue version to the Green by adjusting the weighted values of the target groups. Alternatively, you can instantly switch all traffic by setting one version's weight to 0% and the other's to 100%.
Canary Deployment:
Process: A small percentage of traffic is gradually routed to the new version (canary), while the rest continues using the old version. If no issues are detected, the canary version progressively receives more traffic until 100% is switched over.
Benefits: Allows for gradual testing of the new version with live users. Reduces the risk of wide-scale failures by exposing only a portion of users to the new version initially.
Drawbacks: Slower to fully deploy, as it requires monitoring at each stage. Rollback is more complex than Blue/Green if issues are detected late in the process.
Rolling Deployment:
Process: The new version is deployed incrementally across the infrastructure, replacing old instances one at a time. During the process, both the old and new versions may be live at the same time.
Benefits: No need for duplicate environments, so it’s cost-effective. Suitable for large-scale applications where deployments can be handled in smaller batches.
Drawbacks: Can introduce inconsistency, as different users might see different versions during the deployment. Rollback can be slow and complicated if issues arise after partial deployment.
A/B Testing Deployment:
Process: Similar to Blue/Green, but with a focus on testing different features or versions (A and B) for comparison. Users are split between the two environments to evaluate performance, user experience, or new features.
Benefits: Provides insights into user behavior and performance differences between versions. Allows for data-driven decisions based on real-time feedback.
Drawbacks: May require long-running parallel environments, increasing costs. Not ideal for critical application updates where one version must fully replace the other.
Highlander Deployment:
Process: The new version of the application is deployed across all servers simultaneously. The old version is entirely removed, and only the new one remains active.
Benefits: There is no need for duplicate infrastructure, as only one environment is maintained. With no need to maintain two separate environments (Blue and Green), infrastructure costs are lower.
Drawbacks: If the new version has issues, all users will experience problems simultaneously, with no quick rollback option. There is no opportunity to test the new version in a live environment before deployment.
2. Monitoring and Testing
1. Planning and Preparation
Let's summarize and go over a few recommendations for implementing Blue/Green Deployment in your projects. I recommend the following steps:
1. Planning and Preparation:
Ensure you have a clear migration plan and sufficient resources to support both the Blue and Green environments. Prepare and thoroughly test the Green environment before switching traffic.
2. Monitoring and Testing:
Use monitoring tools to track the performance and stability of the new version. Conduct comprehensive testing in the Green environment to ensure there are no critical errors before moving to production.
3. Automation: Implement automated deployment and traffic switching processes to minimize human error and speed up the migration process. This will enhance the reliability and efficiency of your deployment.
4. Documentation and Training: Train your team on Blue/Green Deployment techniques and prepare detailed documentation to streamline the deployment and rollback processes. Clear guidelines will make the process smoother and ensure everyone is aligned.
4. Documentation and Training
3. Automation
Thank you for your time!
Anton Alputov is a mature IT professional offering 14 years of hands-on experience in the Web industry. Strong knowledge of Java 8-17. Deep knowledge and versatile experience in DevOps, building interactive RESTful Web applications on Spring framework (Core, MVC, Data, Security) and Spring Boot.
I can write SQL queries and have excellent experience in database normalization and optimization. I love writing unit and integration
https://www.linkedin.com/in/alputov/ tests. I guarantee clean code, adherence to SOLID and OOP design patterns. On the last project, I actively worked with microservice architecture on Spring Cloud.
