Many companies lack the expertise needed to avoid workload interruptions when deploying software. To accelerate the software development lifecycle, organizations must find ways to achieve zero downtime application deployments. Zero downtime deployments empower your business to make changes while an application is running.
Ideally, companies can use DevOps practices to take advantage of seamless deployment strategies that eliminate downtime for a faster time to market. For example, continuous integration and continuous delivery (CI/CD) pipeline helps with automating testing and finding problems before deployment. However, a zero downtime deployment can be accomplished by manually building and releasing an application using the right strategy.
Here is an overview of 4 methods for achieving DevOps deployments with zero downtime.
A rolling deployment strategy slowly replaces previous versions of an application with new versions by entirely switching out the environment in which the application is running. For example, containers running new versions of an application may take the place of containers running previous versions of an application.
In a rolling deployment, the infrastructure environments in which old and new applications are being run are not isolated from each other. This lack of isolation means a rolling deployment can be accomplished quickly.
However, rolling deployment has its trade-offs. This strategy requires complex orchestration, and accomplishing a rollback is difficult when backward compatibility is not supported.
To avoid risk, a canary deployment uses a phased approach in which traffic is shifted in increments. With the aid of a router or load balancer, new application code is released to a small group of users so it can be tested. Metrics measure the success of the new iteration.
Once the new version of the application has been accepted, it can be rolled out to the rest of the environment gradually by loading more users. If the new version of the application needs more work, it can be rolled back. Deploying the application slowly prevents the risk of delivering a new version that may negatively impact the workload.
Like rolling deployments, canary deployments can present risks with backward incompatibility. These deployments can also take more time because they are carried out in increments.
Blue-Green deployments eliminate downtime by running 2 identical production environments, one called Blue and the other called Green. Only one of the environments is live at any one time and handles all production traffic.
Blue-Green application deployments reduce risk and enable zero downtime by allowing a company to switch to the other production environment if something happens to the environment that is currently live. AWS users have several options for taking advantage of Blue-Green deployments when they use Auto Scaling Groups (ASG).
Cost is a downside to Blue-Green deployments because duplicate environments must be created with identical infrastructure.
An A/B deployment strategy allows your company to test 2 versions of an application on users. The “A” version would be the old version, while the “B” version would contain a new or revised feature. Each version would be released to a subset of users for testing and feedback.
Once the “B” version has been tested and proven to be sound, it can replace the “A” version. A/B deployments prevent applications with flawed code from being released, necessitating a recall and further recoding.
A/B deployment involves introducing versions of an application to segments of an audience, while A/B testing submits two versions of an application with a single change to determine which version functions best.
A/B deployments can be complicated because companies must calculate a sampling size and observe results carefully to draw the correct conclusions about the best version of the application.
Choosing one zero downtime strategy over another depends on how much time you can spend on testing, how much money you can afford to invest, how flexible your architecture is, and how much time a rollback would take. To experience the benefits of zero downtime application deployments, your company should invest in DevOps.
IO Connect can guide your company in making decisions about which application development tools to implement for seamless deployments. We have established a DevOps practice staffed by our DevOps team, so we can help your company take the right approach to application delivery.
We have achieved AWS DevOps Services Competency because we have demonstrated specialized technical proficiency and have a record of accomplishment of customer success with specific focus on CI/CD, Monitoring, Logging, and Performance, Infrastructure as Code, Microservices and Containers, Serverless, and Configuration Management. This means we can help you leverage AWS solutions to achieve zero downtime application deployments.
Is your company facing downtime during application deployments? Let IO Connect help you choose the right strategy for zero downtime.