Migrate your applications from Microsoft Azure Container Services (ACS) To Azure Kubernetes Services (AKS)


With the Microsoft Azure discontinuation of Azure Container Services (ACS), users have been moving their distributed infrastructures across to the newer Azure Kubernetes Services (AKS). However, the alternative orchestration options such as Docker Swarm continue its storage support for users, Microsoft Azure Cloud Services no longer runs it for them. So the question here is, just how much do you know about the container invasion? What exactly is Kubernetes, and how can you best approach it for migration?

What are containers and why you should care about them?

Containers are used to package and distribute software applications in a way that is isolated from the host operating system and its dependencies. This makes it easier to deploy applications consistently across different environments, such as development, staging, and production. It’s a very common issue for applications to fail to run correctly when moved from one environment to another. Such issues frequently result from configuration discrepancies that underlie library requirements and other dependencies. This is where containers can make a massive difference, as they offer a compact, immutable framework for application packaging and deployment. A container image is a collection of an application or service, its dependencies, and its settings. The containerized application can be tested individually and installed on the host operating system as an instance of a container image. Thanks to containers, developers and IT specialists can now deploy apps across environments with little to no modification. A container virtualizes the underlying OS, giving the app that is running inside of it the impression that it has the entire operating system to itself, including the CPU, memory, file system, and network connections. The variations in the underlying OS and infrastructure are abstracted, allowing the container to be deployed and used anywhere as long as the base image is constant. This particular feature is pretty advantageous to developers. 

What is Kubernetes?

Kubernetes (also known as K8s) is an open-source container orchestration system for automating the deployment, scaling, and management of containerized applications. It was originally developed by Google and is now maintained by the Cloud Native Computing Foundation (CNCF). Kubernetes allows you to run multiple containers as a single unit called a pod, and manage them more efficiently. It provides a declarative API for defining the desired state of your applications and automatically manages the underlying infrastructure to ensure that the desired state is achieved. 

Why use Kubernetes and containers?

Using Kubernetes and containers can help you deploy and manage applications more efficiently and consistently, improving the reliability and scalability of your systems. Using them together can provide several benefits, including the following:

  • Portability: You can run your containerized applications on any infrastructure that supports Kubernetes, such as on-premises servers, public cloud, or even your own laptop.
  • Scalability: You can easily scale up or down the number of replicas of your application, depending on the load, by using Kubernetes’ horizontal scaling feature.
  • High availability: Kubernetes can automatically restart failed containers and reschedule them on healthy nodes, ensuring that your applications are always available.
  • Automatic bin-packing: Kubernetes can automatically place containers on the most appropriate nodes in the cluster based on resource requirements and constraints.
  • Load balancing: Kubernetes can automatically distribute traffic across multiple replicas of your application to improve reliability and scalability.
  • Service discovery: Kubernetes provides a built-in service discovery mechanism that allows applications to discover and communicate with each other using DNS names or IP addresses.
  • Ease of use: Kubernetes provides a simple and declarative API for deploying and managing containerized applications, allowing you to focus on writing code rather than infrastructure management. 

What is Azure Kubernetes Service (AKS) and Why it’s necessary for your business?

When it comes to cloud services, Azure is a widely used cloud platform by organizations of all sizes, from small and medium-sized businesses (SMBs) to major corporations, while Kubernetes is a cutting-edge strategy that is quickly replacing traditional management practices for cloud-native apps in a production setting. Both solutions have been combined into the Micro Soft Azure Kubernetes Service (AKS), enabling users to rapidly and easily build fully-managed Kubernetes clusters. In June 2018, Microsoft Azure cloud computing services made AKS available to the public. AKS is an open-source fully managed container orchestration service that can be used to deploy, scale, and manage Docker containers and container-based applications in a cluster setting. The nice part about Azure services is that you don’t need extensive knowledge and skill in container orchestration to run AKS. AKS allows resource provisioning, scaling, and upgrading according to requirement or demand without any downtime in the Kubernetes cluster. The burden of deploying and running apps on the Kubernetes architecture is lessened thanks to Azure Container Instances. AKS is also completely compliant with the standards and regulatory requirements such as System and Organization Controls (SOC), HIPAA, ISO, and PCI DSS. When looking to migrate your applications from Microsoft Azure Container Services (ACS) To AKS, there are a number of guidelines that you must follow. In the next sections, we will discuss Azure cloud computing migration tips and also find out how you can get hold of the best Windows cloud hosting in India. 

What will happen to the existing ACS apps?

Microsoft Azure Services have assured the application build on the ACS will not stop running suddenly after the ACS gets outdated. However, the APIs that manages the application will be blocked, so the users will have no control over the applications and will not be able to use Azure tools to add or update new clusters or even scale the existing services. There will be no support from the Microsoft Azure team, even if the user tries to manage the running codes using their own tools as it will put a limit over the capabilities. 

Preferably, users will be locked into the older versions of the current orchestration framework and will not be able to rely on the automated security updates, so far. Thus, to help and assist the users to carry out successful migration of their applications, Microsoft Azure cloud services will provide a reliable base for Azure Kubernetes Services (AKS). Since the underlying orchestration concepts and tools are different for the alternatives, each having different container models, significant code change will be nearly impossible while migrating the applications. 

Know how to migrate from ACS to AKS

First of all, it is very important to consider the economic perspectives of the migration. Moving from ACs to AKS or towards an open source version of Mesosphere DC/OS should not have a consequential impact on billing. If the user wants to migrate towards the Docker Enterprise for Swarm or the Enterprise release of the DC/OS, license for the same is required along with the infrastructure cost of the Azure Services. So, it is advisable to opt for AKS to have one monthly payment method.

Also, once the user decides to move from Docker Swarm or DC/OS to ACS instance, working with the full product does not require any significant engineering effort, at all. 

Moving Kubernetes from ACS to AKS

AKS has added a lot of management feature on Microsoft Azure cloud computing services from the past year as it has matured and grown. Hence, it has become one the most promising solution for deploying Kubernetes-managed applications on Azure.  Features like virtual Kubelet via Azure Container Instances support AKS to take advantage of ACI’s higher level container management, eventually reducing the workload associated with the existing Kubernetes to a great extent. 

Although, issues exist while moving Kubernetes from ACS to AKS that might require some changes to be done to the application architecture, helping users to handle the differences between ACs and AKS. Since AKS is a managed Kubernetes, it needs to be handled well to smoothly run the application. With the help of Azure Managed Disks, AKS controls the storage directly by adding capacity as required. 

Users need to upgrade the Kubernetes version they are using for their code that can be handled well in a development environment. After deployment, the application gets managed by the control panel of AKS with support for dynamic scaling. Also, the user must check for the AKS APIs support as there are API differences between AKs and ACS for monitoring and debugging.  

Managing Kubernetes Storage and Deploying to AKS

While migrating a stateless application form ACS to AKS, users can deploy the process onto a new cluster and let AKS deploy and start the containers. Once the cluster runs, the code can be tested before switching public IP addresses from the ACS instance to AKS. 

Whereas, the complication occurs with stateful applications where the users are alerted for possible extended downtime. Users can set up a failover replica of the application on AKS or let it replicate the critical data. Once the data syncs with the existing ACS application, it can fail over from the ACS application to AKS, before redirecting the traffic to AKS. 

Migrating the storage to managed disks is a tedious task and require significant downtime if the data is heavy. The user first stops the ACS code writes, shut it down and take a snapshot of the disks. The snapshots are then used to create new disks that are used as AKS Persistent Volumes. Once deployed, the application is tested before sending the traffic to the AKS. 

The method to deploy the code to AKS is almost similar to deploying code to any other Kubernetes cluster. Users start by creating a cluster in AKS, using similar node definition as used in ACS. Then edit the code to support the AKS definitions and locations, and deploy the existing CI/CD pipelines to the new service host. Once the code gets updated, it is tested using the existing test tools and techniques before migrating the users to the new service.

Final word

Now the users are all set to take advantage of a fully managed, auto-scaled environment using the support of Virtual Kubelets and get automatic updates. This protects the users from security issues. Microsoft’s latest addition of the Kubernetes update is certain to take the storage technology to another level. Nevertheless, at the same time, to get the most out of your migration plans, you must work with a leading microsoft cloud service expert with proven experience. If you are also looking for such updated cloud and storage services for your application to keep up with the pace of transforming business landscape, we at i2k2 Networks are here to help you. Being a 20-year old trusted Microsoft Azure service provider in India, we offer a full range of Deployment Planning Services (DPS) for Microsoft Azure Cloud Computing – giving the best of both the worlds – PaaS and IaaS. Not only that, but we also provide Amazon cloud services. To work with the leading web hosting company Noida, call us at +91-120-466-3031 | +91-971-177-4040 or can write to us at sales@i2k2.com.