OpenShift Architecture is a ready Kubernetes distribution but with extra features. In the backend of the OpenShift Architecture, we can see the same Kubernetes orchestration system which automates the management of applications.
OpenShift Architecture. Is it better than Kubernetes?
OpenShift is a system of layers, where the layers are tightly connected with each other. OpenShift uses Kubernetes and Docker clusters to connect the layers together. Similarly, Red Hat has designed this software to support Docker containers.
There are various versions of OpenShift software. The latest version is OpenShift V3 which has a new feature to manage containerized infrastructure. Kubernetes and Docker play an important role in OpenShift Architecture. Therefore, OpenShift is also known as a container platform software.
Advantages of OpenShift
- Consistent Security.
- Built-in monitoring support.
- Compatible with Kubernetes system.
- Supports programming languages like Ruby, Python, PHP, etc.
Docker containers are present in the OpenShift Architecture. OpenShift uses Kubernetes to maintain these containers. Kubernetes is the main component of this architecture because it manages this infrastructure. Kubernetes clusters consist of multiple nodes and a master node that manages the architecture and makes sure the setup does not fail at any point.
This component collects the configuration details which is required by each node. OpenShift distributes the key-value store among multiple nodes. Kubernetes API server is the only one who can access the Etcd component because the configuration details are too sensitive. Similarly, it also has a distributed key-value that any node can have access to.
Kubernetes in the OpenShift Architecture has an API server. This API server holds all the operations that are used for the nodes to perform some actions. In addition, the API server consists of various tools and libraries. These libraries can communicate with the nodes with the help of interfaces. For instance, to communicate with the nodes a server-side tool uses the kubeconfig package.
The Controller Manager keeps an eye on the Etcd that collects the state of the cluster nodes and performs a task accordingly. The Controller Manager flows in a loop that is non-terminating.
The main purpose of Controller Manager is that it collects the information from the cluster and sends it to the API server. Therefore, OpenShift has designed this component to change the present state of the server to the desired state. To manage the nodes and endpoints the controller manager deploys different controllers such as:
- Service account controller.
- Replication controller.
- Endpoint controller.
- Namespace controller.
The master node has to distribute the workload between other nodes to complete the task. The scheduler is the key component to perform this action. Similarly, it is the service component that is responsible for the distribution of tasks among the nodes. It also monitors each node to check the assigned tasks. It tracks both workloads of the node and also the resources on which it is working and distributes the task according to the resources required to complete the task. If a new node is added to the cluster, the scheduler is responsible to allocate the workload to the new node.
OpenShift Architecture– Slave Node Components
The Slave node needs to communicate with the master node. Therefore, the node server is divided into 3 key components.
Dockers are the containers that encapsulate the application to execute in a lightweight environment. Therefore, each node requires a docker.
Each node has a small service component known as the Kubelet service. It plays an important role in sending and receiving the information of the node. Similarly, it collects the configuration information from the Etcd. Kubelet also communicates with the master node to receive operations and tasks.
Kubernetes Proxy Service:
This component is responsible for the availability of services on each node to the external host. Proxy Service transfers the request to the desired containers. It is also capable of balancing the workload of the nodes.
OpenShift is a scalable platform. We can use the OpenShift platform in VR, cloud computing services, and on-premises. OpenShift has a feature of containerization. When we transfer all our applications on OpenShift they can also get the advantages of containerization. However, the best feature of OpenShift is that we can implement Machine Learning and AI functions.
To increase the security you can also use third-party security vendors because OpenShift is pluggable. Most of the public cloud companies like Azure, AWS, etc use the OpenShift platform
We have seen that Kubernetes is the backend of the OpenShift platform. OpenShift is not an alternative to Kubernetes. Both have different features and properties. Here are some of the differences between them.
Cloud Computing Services
Kubernetes performs actions on the container images. It does not support the creation of containers alone. Kubernetes requires additional APIs to build the container image. In conclusion, Kubernetes is a Container as a Service(CaaS).
On the other hand, OpenShift is a platform that can create and maintain the container. It has inbuilt properties to create and store images. Hence, it is a Platform as a Service (PaaS).
We have seen that in Kubernetes the containers are built separately and that we have to test and monitor the process of the application. This is a manual process or else you will need some additional APIs to perform these tasks automatically.
OpenShift has built-in API libraries that support the entire application lifecycle. It has also some inbuilt tools that can create the workflows of the process.
Kubernetes supports many Linux operating systems such as Fedora, Red Hat, Ubuntu, etc.
OpenShift only works on RHEL and RHCOS operating systems designed by Red Hat.
Kubernetes has strong security. The rules are flexible but meet the requirements.
On the other hand, OpenShift security is stronger as compared to Kubernetes. The user has to read the terms and conditions before creating the application on it.
In conclusion, OpenShift is one of the most popular container management systems. It is the same as Kubernetes system but has some unique features. We can run the application on OpenShift more efficiently with the help of Kubernetes.
Red Hat has developed the OpenShift Platform. It has a free trial subscription to try the software. OpenShift is a well-developed software that supports various programming languages like Node.js, Java, Python, PHP etc.