Kubernetes is an open source container orchestration system for automating computer application deployment, scaling, and management. It was originally designed by Google and is now maintained by the Cloud Native Computing Foundation.
So let’s jump in and see what some of the best practices for writing Kubernetes applications are.
One of the best practices in Kubernetes is scaling. Kubernetes’s autoscaling feature allows you to automatically scale cluster services with a surge in resource consumption.
Kubernetes has three types of auto-scaling deployments: vertical pod autoscaler, horizontal pod autoscaler, and cluster autoscaling. Vertical pod autoscaling recommends and can automatically update the best values to be set for CPU and memory requests and limits.
The horizontal pod autoscaler adjusts the number of pods, volume, and nodes in a replication controller, replica set, or stateful set based on CPU usage. As a result, the load is kept at an optimal level, and capacity downtime is avoided.
The cluster autoscaler expands and contracts the pool of worker nodes. It changes the size of a Kubernetes cluster based on current utilization.
As a result, the load is kept at an optimal level, and capacity downtime is avoided.
2. Enable RBAC
Role-based access controls (RBAC) help administrators give and restrict access to particular users and groups and define who can do what on the Kubernetes cluster. To enable RBAC permissions for Kubernetes resources, we must provide Kubernetes with a role for a namespaced resource, and a ClusterRole for a non-namespaced resource
RBAC also gives an extra layer of security by making administrative rules, giving or taking permissions, providing access to user, and allowing role binding and cluster role binding
3. Maintain Small Container Images
As a best practice, you should always use smaller container images as it helps you create faster builds and save time. Use Alpine Images, as they are 10x smaller than the base images. By using a small image, you can reduce the size of the application. Large images, on the other hand, will make your application unresponsive and slow.
Adding unnecessary libraries and packages to the application will, unfortunately, increase its size. It is always suggested to use the necessary library and packages for your application only.
Advantages of using smaller container images are faster builds, less storage, faster image pulls, and potentially reduced attack surface.
Bonus tip: Instead of going to the Docker hub and taking any basic image that someone has created, create your own image because the image you use may contain an unnecessary library that will, unfortunately, slow down your application or introduce a malware or bug you didn’t notice.
4. Label Your Metrics for Easier View, Aggregation, and Analysis
Labels function like key-value pairs attached to objects such as pods. They are intended to be used as distinguishing characteristics of objects that are important and meaningful to users. Label your metrics to facilitate viewing, aggregation, and analysis. Labels are a part of Kubernetes best practices.
5. Set Network Policies
Setting network policies allows us to decide and control traffic, and manage what traffic is permitted and what is not, allowing us to restrict and limit unwanted traffic. Essentially, network policies determine whether to allow or restrict a particular connection.
6. Kubernetes Resource Usage
As a good practice, we can specify resource requests and limits for individual containers.
Kubernetes resource usage examines the number of resources used by a container or pod in a Kubernetes environment. Without resource requests and limits, pods in a cluster may begin to consume more resources than necessary, causing the node to crash. To avoid this, it is important to monitor the resource usage of pods and containers.
The minimum amount of resources that a container can use is specified in resource requests.
The maximum amount of resources that a container can use is specified by resource limits.
7. Monitoring and Logging Your Applications
When working with Kubernetes, it’s difficult to keep track of your deployment. However, it is critical to maintaining the security of the configurations, performance, and traffic. It is impossible to diagnose problems without logging and monitoring. Monitoring and logging are required to ensure compliance.
8. Download the Latest Version
Kubernetes releases new features, bug fixes, and platform upgrades with its regular version updates. You should always use the most recent Kubernetes version on your cluster.
9. Use Namespaces
By default, Kubernetes has three separate namespaces: default, kube-public, and kube-system. Namespaces are essential for organizing and securing your Kubernetes cluster from other teams working on the same cluster. For example, if your Kubernetes cluster is vast (hundreds of nodes) and numerous teams are working on it, you must have separate namespaces for each team. In this manner, each team has its own access that doesn’t interfere with other people or the production environment.
The practices mentioned above are the most crucial when writing Kubernetes applications. However, you can also add on things, like using declarative APIs, using an SDK, using version control for configuration files.
I hope you found this article useful! Thanks for reading!