Kubernetes is an example of the most powerful tools in the DevOps field that involves containerization in an IT architecture. At present, about 80% of IT organizations adopt Kubernetes in their production environment. And it helps with container orchestration, load balancing, scaling, and more. Kubernetes makes the containerization of applications easier, but it is not easy to use, especially for beginners. If you are working with different Kubernetes clusters, you will find various difficulties while managing them together. That’s why you need to follow the best Kubernetes Configurations Practices to manage the Kubernetes clusters better and more effectively.
1. Keep Kubernetes Updated to Its Latest Version
You always need to keep your Kubernetes version updated, and it’s not an option. If you regularly update your Kubernetes deployments, it will help you add more new and interesting features to your application containerization. Every new update of Kubernetes deployments comes with a bunch of security features and resolves various glitches from the previous version. And since the older versions of Kubernetes do not get enough support from the community, you need to make sure that your Kubernetes version is always up-to-date.
2. Version Control for the Configuration Files
Before you release the configuration files to a cluster, you need to store them in a version control system. These files can be related to deployment, services, and ingress. If you can keep track of these files, you can easily keep a record of the changes made to these files; thus, you can implement the change approval processes to make sure your Kubernetes cluster is secure and more stable.
3. Use Pod Security Policies
In Kubernetes, there is a cluster-level resource available that is known as PodSecurityPolicy that is available through kubectl. To use the cluster-level resource, you need to enable the PodSecurityPolicy controller. You need to authorize one policy in the cluster if you want to create pods in the Kubernetes cluster. The PodSecurityPolicy has numerous use cases, including the following:
- The security policy prevents containers from running with the privileged flag.
- Does not allow you to share networking, ports, host PID/IPC namespace, etc. so that there is genuine isolation between the containers.
- It limits the use of volume types, for example, host path directory volumes.
- Enforces read-only in the root file system.
- Prevents privilege escalation on the root.
- Rejects containers that have root privileges.
- Restricts Linux capabilities to provide the least privileged principles.
These security controls are possible through pod security policies that ensure the security of your containerized applications.
4. Use Kubernetes Namespaces
You can generate logical partitions and separate your resources using namespaces. Namespaces also put a limit to the user permissions. In Kubernetes, there are three types of namespaces which are default, Kube-public, and Kube-system. If you have multiple teams working on the same Kubernetes cluster, you can use namespaces to keep them organized and separated. If there are over thousands of nodes in the cluster, and different teams are working on the cluster, you should have multiple namespaces for each of the teams. You can generate development namespaces, deployment namespaces, testing namespaces, etc., for different teams. If you organize the namespaces like this, then the different teams, like the development teams, won’t be able to create any changes to the testing namespace. If you don’t create separation, then you might also make some mistakes in the cluster.
5. Use Labels
In the Kubernetes cluster, there are services, containers, networks, pods, etc. You need to maintain these elements in the Kubernetes and keep a record of how they communicate with each other, and the process is troublesome. That’s why labels help you organize your Kubernetes cluster, and these labels come with key-value pairs that make it easy for you to organize the cluster. For instance, if you are running two similar elements of the same application at the same time, you might also have multiple teams to look after their components. Labeling the elements differentially will help you showcase the ownership of the elements effortlessly.
6. Establish Resource Requests & Limits
Sometimes deploying software to a Kubernetes cluster can fail if the resources are limited, and this situation is not very uncommon. This situation mostly occurs when the requests and resources limits of the cluster are not properly established. If you don’t put a proper limit on the resources, then the pods won’t utilize more resources properly. Also, the pods can consume more CPU memory, and the scheduler won’t be able to create new pods. You can set the resource request limits to the minimum number that a container should use. Or you can mention the highest number of resources a container can utilize.
7. Readiness and Liveness Probes
Readiness and liveness probes are mostly health check-ups on the cluster. Readiness probes make sure that a particular pod is running properly and directs a load to the pod. If the pod is not running, then the requests won’t be live anymore on your service, and wait for the pod to be ready. The liveness probe verifies if the application is working properly and checks in with the pod to make sure its status is updated. If the probe does not get any response, then the software is not running on the pod. The liveness probe creates new pods and starts the software on them if it is unable to check-in with the previous pod.
8. Use Container Images but on Smaller Sizes
Some developers include base images on the containerization that includes most of the packages and libraries that are unrequired. In that case, we suggest picking smaller container images that don’t take much space on the cluster and also make it easier for you to pull and build the image quicker. Small docker images contain fewer risks when it comes to security.
9. Monitor Your Control Panel
Don’t make the mistake of not monitoring the control panel and its components that include Kubelet, Kubernetes API, controller-manager, Kube-proxy, etc., and kube-dns. These are the main components of your cluster that you need to monitor every day to keep up with its performance. In the Kubernetes control panel, some metrics are used in the Prometheus format that creates alerts when the components go through any sort of issues. When you monitor the control panel components regularly, it helps to keep the resource consumption and the overall work volume within limits.
10. Audit Logs Regularly
The logs in the Kubernetes cluster help you identify threats and vulnerabilities in the cluster. You should store and audit these logs regularly and properly to make sure your cluster is safe. The logs and request data of the Kubernetes API are saved in the audit.log file, and the location of the file is /var/log/audit.log, and the audit policy is saved at /etc/kubernetes/audit-policy.yaml.
Conclusion
Even though using Kubernetes containerization is easy for most beginners, you need to make sure that you are using it right. Kubernetes containerization is constantly getting upgraded, and if you can’t use it successfully, you won’t be able to get the best out of it. Applying these best Kubernetes configurations practices will help you achieve the best sense of containerization using Kubernetes. If you desire to study more about Kubernetes, check out our other articles.