A blue-green deployment strategy is the perfect solution for when uptime is critical. It's a technique that minimizes system downtime and risk by running two identical production environments called blue and green. For example, the blue environment is currently live and the green instance is idle. When there's a problem in one environment, engineers can switch to the other in order to maintain uptime in the event of an emergency.
As you prepare for an updated release of your software, deployment and testing will take place in a test environment that won't affect the live system. Once your new code is ready, you'll switch the router so all incoming requests go to the new version in the test environment instead of the live system. The new version becomes the live system, and the older version becomes idle.
The idea behind blue-green deployments is to reduce the risk of downtime during deployment. This technique can also lessen the amount of time it takes to roll back an app if something goes wrong. Should anything unexpected happen with the new version, a business can immediately roll back to the last “green” version by switching back to the “blue” one.
When a new software update is released, a business must determine whether they want to adopt it immediately or roll out in stages. This process is known as a "blue/green deployment," and it has a few benefits. A use case is if a software development update doesn't work well, the company can roll back to the previous version instantly at any given time, preventing any major problems from happening and allowing for fast disaster recovery.
The biggest advantage of this deployment process is zero downtime. There is almost no drop in service with the new changes, and clients don't notice when they switch to the new environment.
Blue-green deployments are a modern approach for DevOps teams to introduce new features. A blue-green deployment is an approach that ensures you won’t blow up your production environment when introducing new features. Even if that would happen, you can easily roll back the router to point to an earlier environment. All you have to do is "flip the switch”.
If you have an application that doesn't store any data, then you can start doing zero downtime deployment. Unfortunately, most software stores data, which means that you need to think about making schema changes before doing any sort of deployment.
With blue/green deployment, engineering teams can always ensure they have a working version of the website ready. If something goes wrong with the green version, they can switch back to the blue version and address the issue at a later date. This is ideal if an issue arises at an inconvenient time like the end of a long workday or on a Friday evening. With blue-green deployment, the issue can be resolved the following day or on a Monday morning.
While blue/green deployment is risk-free, there is an even safer strategy; canary releases. The canary deployment strategy uses rolling deployment which involves testing your code on only a subset of user traffic before rolling it out to the entire user base. This allows DevOps teams to avoid any mistakes in production or performance issues while making changes to their codebase based on testing in a live environment.
Using the method of canary tests, you can deploy a new feature to 10% of your visitors first to test the bugs before deploying the new update to 100% of your users. When releasing a new version of your site, it's important to have a controlled blast radius. A new release doesn't have to immediately switch 100% of your users over to the new version.
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In the current fast-paced world, testing software is a never-ending task. The only way to stay on top of it without getting too overwhelmed is with CI/CD. This lets developers quickly find and fix bugs and ensures that updates are made gradually and carefully.
Blue-green deployment is about having two identical environments, in front of which there is a router or load balancer that allows you to direct traffic to the appropriate environment. This type of deployment is quite useful because it ensures uninterrupted service if one of the environments goes offline.
The other great benefit of this approach is that tests are performed in production. This allows developers to work with a full environment, which makes them confident the application will work as expected. If it doesn't, there's still an easy way to revert back to the old version.
DevCycle is a feature management tool that allows you to leverage feature flags to ship faster, reduce risk and maximize the impact of your blue-green deployments. By leveraging feature flags, you can increase your release cadence by minimizing release complexity.
Through continuously deploying and testing in production, you can organize your feature flags in several environments with our APIs without needing to leave your workflow. Developers, product, and marketing teams can toggle a feature on or off in the DevCycle dashboard to control who has access.
DevCycle also enables you to maximize the impact of your blue-green deployments through zero latency experimentation build for developers. Iterate and optimize features with the ability to dynamically modify content in production without redeployments.
Development teams can employ continuous integration and continuous delivery to keep up with the competition. This practice will allow for faster development cycles, as well as the ability to deploy new features without risk of errors. Practices like blue-green deployment can also help mitigate risk and save developer resources while creating a better user experience.
Want to use feature flags best practices to start implementing blue-green deployment and improve your software delivery workflow? Get started with a free trial of DevCycle.
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