A Simple Guide to Cloud Migration With Kubernetes
Migration to a public cloud environment enables companies to avoid the overhead associated with on-premises infrastructure. In addition, cloud migration helps organizations to get visibility into application traffic, plan a solid disaster recovery strategy, and improve security.
Container orchestration platforms like Kubernetes can help developers migrate an application container to the cloud, since containers package application components in manageable block units. This article walks you through the process of migrating applications to Kubernetes.
What Is Kubernetes?
Kubernetes is an open-source container and microservices orchestration tool developed by Google. Kubernetes offers a highly resilient distributed infrastructure with zero downtime deployment, scaling, automatic rollback, and self-healing of containers.
The main purpose of Kubernetes is to simplify the management of containers by providing REST APIs for the required functionalities. You can also use Kubernetes as a Service (KaaS) solutions to run clusters on different private or public cloud environments like Azure and AWS, and management platforms like OpenStack or Apache Mesos. Kubernetes can also run on bare metal machines.
Why Use Kubernetes
Migrating to a container-based cloud environment like Kubernetes enables you to implement hybrid cloud and multi-cloud platforms, and handle large workloads and unexpected failures.
Vendor-neutral
Public cloud providers offer a lot of container orchestration products built on top of their managed Kubernetes services. Organizations that take the vendor-agnostic approach can build, design, and manage hybrid cloud and multi-cloud platforms without the risk of vendor lock-in. Kubernetes enables you to easily implement your multicloud or hybrid cloud strategy.
Elasticity
Handling large workloads in cloud environments requires autoscaling capabilities. You can increase the scaling abilities of your system by building a container platform. Kubernetes Horizontal Pod Autoscaler (HPA) enables clusters to reduce or increase the number of running applications during performance spikes or peak traffic times. Thus reducing unplanned system outages issues.
Resilience
Handling failures with dedicated code is vital for controlling and recovering from unexpected errors in modern applications. However, developers invest a lot of time and effort to simulate all (or as many as) possible errors. ReplicaSet helps developers overcome this challenge by constantly maintaining a specified number of running pods.
Service discovery
Microservices developers must control the availability of their applications to serve a function. In addition, they need to ensure that the service continues to run without any exceptions, in response to client requests. Kubernetes’ service discovery feature manages these things to enable developers to spend more time on development tasks.
How Kubernetes Can Help With Cloud Migration
Containers are standard units of software that package all the necessary code and dependencies to run an application. Developers can use containers to deploy applications easily and faster. Benefits of containerization include:
- Scalability — pods serve as replication units in Kubernetes. Pods consist of several containers deployed together. A cluster is a group of nodes that receive pods. Adding pods to a cluster can help you easily scale up your application.
- Portability — containers simplify the software development and deployment workflow, by enabling you to run software across different cloud environments.
Companies often end up with multiple containers that require management, deployment, and connectivity in a cloud environment. Container orchestration platforms like Kubernetes help developers manage large numbers of containers.
Developers can easily migrate an application container to the cloud since containers package the application components in manageable block units. Manual management of containers can be challenging, this is why developers use Kubernetes to orchestrate systems.
Cloud Migrations Strategies for Kubernetes
The list below reviews the most common migration strategies to a container management platform in the cloud.
Rehosting
Rehosting, also called lift and shift, is the simplest approach to cloud migration. Entire applications and web services, including all components are moved into a Kubernetes cluster. The rehost approach involves wrapping up a container around your app and then deploying by configuring Kube yaml files. This method is the fastest way to move to Kubernetes in the cloud because you do not need to make any changes in your app.
However, rehosting is not the most efficient way to utilize the cloud environment offered by Kubernetes. You do not get all the benefits and flexibility of Kubernetes right away. But you can further break down services and parts of the app into additional nodes after the completion of the initial cloud migration.
Replatform
The replatforming approach requires the preparation of the app for migration, as well as making some basic changes to the way the app operates. The migration process usually involves the separation of services and functions into individual containers and pods. Using the same app with different configurations is a quick way to replatform services.
Replatforming takes longer to complete than rehosting, because adapting apps to a container-based cloud environment is a complex process. You can simplify the process by using a local Kubernetes cluster and Minikube.
Migrating to a cloud cluster like Azure or GKE becomes easier when the updated version is ready and the scloud cluster is laid out. You can even test your app in Minikube, to ensure a smoother transition.
Refactoring
The refactoring approach requires modifying the entire app and supporting services. A refactoring migration process enables you to fully leverage the advantage of the cloud environment by rearchitecting the entire app. For example, you can use cloud-native frameworks, such as Knative, to rebuild services that are designed to work with Kubernetes. The refactoring approach also enables you to run serverless workloads in the cloud
A downside of this approach is significantly longer migration times and additional resource requirements. The main benefit of refactoring is that you get a fully scalable and cloud-native app. Use this process only if you need your codebase to support a major version upgrade, or if you need to go completely cloud-native.
Conclusion
Migrating to a cloud-based container orchestration platform like Kubernetes presents many benefits and challenges for developers. Choose the migration strategy that works best for you by evaluating the objectives and the characteristics of the application.
