Kubernetes Architecture: An Overview
Kubernetes aims to simplify the management and deployment of services including creating applications as a set of independent services. The key concepts in Kubernetes can help to scale distributed applications. The components of the Kubernetes make the orchestration platform more scalable and effective. Knowing the principles of Kubernetes and how components interact helps a lot. As many IT industries have been adopting the Kubernetes ecosystem to attain digital transformation, adeptness in Kubernetes architecture help solve problems and optimize workflow in a yielding manner.
Kubernetes Components
Kubernetes is simply a container orchestration and consists of many components such as a control plane and worker nodes. The Control plane is a computer where you install Kubernetes. On the other hand, worker nodes are designated computers to run Kubernetes. Kubernetes consulting in US elucidates components of Kubernetes as follows:
Control Plane components
- ETCD
Etcd is a backing store that is used to keep Kubernetes object data such as services, secrets, pods and replication controllers. Etcd communicates with the Kubernetes API server. Cluster data and metadata can be secured using ETCD. Scaling ETCD is possible in Kubernetes architecture.
- API server
As we have seen, Etcd alone directly interacts with the API server in order to operate the cluster state. API server delivers many functions in Kubernetes architecture. It stores Kubernetes objects in ETCD along with validation of those objects. Apart from managing Kubernetes objects, the API server is responsible for any client request and optimistic concurrency locking. It also has a watch mechanism similar to ETCD.
- Control manager
With the help of control managers, developers can identify if there is any change required in cluster management. The control manager is responsible for the desired state of the cluster as it tracks the Kubernetes resource type. Node controller, Endpoints controller, service controller are some examples of control managers. It also depends on the watch mechanism to get notifications regarding changes in the cluster.
- Scheduler
The scheduler takes care of pods and nodes. It is responsible for newly created pods as well as no nodes assigned. The pods run on selected nodes by the scheduler. Once the scheduler finds an appropriate node, it runs the required set of functions at the same time notifies pods.
Work Node components
- Kubelet
Kubeleet manages everything that happens in each node in the cluster. It ensures containers run on pods, monitors the API server as well as restarts containers whenever the probes fail to notify pod termination.
- Service Proxy
The communication between pods can be achieved with the help of Kube — proxy or Service proxy. Pod definitions and changes on services in nodes are managed by service proxy.
- Container runtime
Container runtime fetches container images, prepares container mount point and retrieves metadata from container image. There are two categories of container runtime.
- Lower-level container runtimes
- Higher-level container runtimes
Conclusion
Kubernetes is now considered the last word for container management for businesses. Containers offer fast and flexible deployment, fine-grained resource sharing and lightweight performance isolation. As new use cases and tools appear every day, building a scalable Kubernetes system becomes difficult. With the help of a Kubernetes consulting company in US, you can also have a robust Kubernetes architecture that targets different use cases as well as APIs. Load balancing, security, networking and service discovery are the different sets of challenges that can be addressed using Kubernetes. In short, configuring and securing a robust infrastructure is arduous and needs meticulous planning as many decisions apart from tools can be selected as per your requirements.
