What is Kubernetes?
Most applications require dependencies to run properly. These dependencies can be operating systems, networking, internet access, or even temporary files on a local drive. Before container services, it was a nightmare for IT departments to maintain the various dependencies. Containers are a viable solution to help manage these dependencies. Two popular container solutions are Docker and Kubernetes.
Another benefit to containers is that configurations are isolated from one container to the next. Before using containers, changes made to a server or virtual machine for one application could adversely affect the operation of other applications. That situation has been solved with the use of containers. This solution allows the coexistence of many applications on a single server or VM without worrying about conflicting configurations.
This article focuses mainly on what is Kubernetes, and Amazon AWS has an implementation of Kubernetes that offers further benefits for AWS subscribers.
Kubernetes is more than a container service.
It is considered a container orchestration service. It can manage several containers simultaneously and offers scaling and failover features.
Kubernetes works as a cluster of systems, with a control plane and one or more worker nodes. These worker nodes contain a module called Kubelets that communicate with an API of the control plane. The control plane manages the workloads and applications. It's configured using a file in Yaml format. The control plane also monitors each worker's health and will replace nodes when necessary and is also responsible for scaling the workloads.
If you currently have a Kubernetes solution running and are considering migrating your applications to AWS, you could port the Kubernetes installation. It may take a few configuration tweaks to get it working properly, but this is a viable option. However, you would be missing out on the benefits of a managed solution offered via AWS.
AWS Elastic Kubernetes services (EKS) is a fully managed Kubernetes service. You won't need to install any software or implement maintenance upgrades. Amazon manages most aspects of the solution. Further, you will benefit from the cloud-native features.
You will not have to worry about your existing Kubernetes software being compatible with EKS, as the AWS option is a fully-working Kubernetes installation. The migration will be seamless and requires no coding changes, which can save money and time.
Another option is the Amazon Elastic Container Service. But with this option, you must manage and pay for ECS components required to run this solution. That entails provisioning virtual machines and networking options. It also does not take advantage of optimizations available through EKS. Further, ECS is not a Kubernetes solution. The container orchestration included in ECS is proprietary software, which could cause issues with compatibility.
Companies implementing EKS are charged a flat rate per hour. At the time of this writing, Amazon published a rate of ten cents per hour. However, this is subject to change. If containers include other services like EC2 to run, these will be charged via standard pricing associated with those services. ECS has no upfront fees, but companies are charged for the services needed to run workloads.
Fargate is an AWS service worth mentioning. AWS subscribers can use Fargate to deploy workloads to containers, but the applications are serverless. The advantage of this option is that you don't have to provision any servers. You are charged for the compute resources that you consume. However, Fargate is not a container orchestration solution, which means companies will not gain the full benefits associated with orchestration. ECS is configured by default to deploy services using Fargate.
AWS subscribers are responsible for securing the services they implement, which is true of any container software implementation. A general rule for any AWS application is to use IAW roles and never implement containers or processes within the containers using the root user. If hackers get access to the root node, they can implement unwanted changes to your Amazon account, and they may cause damage before you realize that a change occurred. IAW can help to limit the damages caused by the bad actors.
Businesses should also stick to secure repositories for images. Administrators often use images of configurations to implement their container orchestration solutions. These images are templates that can make configuration easier than trying to create the environment from scratch. Many free images are available for administrators to use, but publicly available images can be risky and often contain malicious scripts or code. Amazon offers a secure registry for images that are free from these security issues. This is the safest route when using predefined images. It pays to understand how AWS security works when considering security for your installation. This knowledge will help when securing your container orchestration solution.
EKS does have some security features built into the solution. However, that does not prevent users from implementing incorrect security roles or using the root user. AWS completely manages the security features that are provided, which means that users will not have to apply updates or patches.
If your organization currently has a Kubernetes solution running, the most viable option is likely to be EKS. However, the option is more complex than the other options, as it offers more granular features. Administrators will need to understand what cloud-native services are inherent with the solution to benefit from their use.
At Eplexity, we'll learn about your current needs and work with you to find the right container solutions. Our AWS & DevOps experts will work with your IT group to co-manage your cloud Kubernetes service and partner with you to maintain the solutions. Give us a call today to get started.
