We have learnt that Kubernetes is a Container Orchestration system which can be used to efficiently manage and deploy many containers at scale. In order to setup Kubernetes successfully, we require:
Download our infographic here to refer back to the core concepts learnt on this platform.
Let's Explore Kubernetes one final time, following the end to end process. We can remind ourselves of the preparation activities needed by the developers, and follow through how a user request travels through the system and is managed by the Control Plane.
Developers write their own Dockerfile to create the Image for parts of the application they have written themselves and use community or vendor Images for parts they don’t want to create from scratch. They group these together in a pod.
Tommy creates his secret patty recipe and gives this to the prep chefs in the kitchen who gather these with any other recipes needed to make components of Tommy’s burger.
Kubernetes needs to know how to handle each type of request made to the application, so developers define this in a Workload. They include details such as how many containers are needed and what customisations can be made.
The prep chefs write a detailed menu which includes a description of how each dish is made and what can be customised in each dish.
A user submits a request to carry out a batch job, such as requesting to apply the 'noise reduction' audio effect to their audio file.
Two customers place an order to the receptionist on the front desk. One asks for Set Menu 2= burger (with extra bacon) + dessert + drink and the other asks for Set Menu 1= burger + salad + drink.
The Kubernetes API captures the request and writes it to the etcd database, where the Workload definitions are stored. The Workload makes the system aware of what the desired state is (which in this case is a pod running the 'noise reduction' audio effect container).
The receptionist captures the order and writes it down in the database on her computer. This alerts all staff on their ipads that a new order has come through.
A Controller Manager is assigned to ensure the request is successfully executed. It constantly tries to match the current state of the cluster to the desired state of the cluster.
A dedicated waiter ensures the successful execution of orders by consistently checking in on customers, referring back to their order details from the menu to fulfill their expectations.
The scheduler finds a Worker Node with sufficient capacity to be able to run the required containers in.
The maitre’d finds a suitable table with enough seats to seat both customers.
The Kubelet communicates with the Kube API to obtain the relevant Workload and ensure that it is running as desired. It starts and stops the containers as required, monitors their health and reports the state back to the API who logs the state in etcd.
The table chef receives an alert on his ipad from the receptionist which explains the order. He starts cooking their burgers, and provides updates on his ipad so everyone is aware of how far through their order they are.
Inside the container on the Worker Node, the code processes the batch job request and generates the response, such as outputting the audio file with the applied noise reduction audio effect. This response is displayed to the user.
The meals are served to the customers once they are ready.
- We now have a defined, automated way of handling any request within Kubernetes.
- When we receive a larger number of requests, Kubernetes gives us the ability to scale and handle this growing load automatically.
- In periods of lower demand, Kubernetes scales back down to reduce unnecessary costs.
- If a container or worker node fails, Kubernetes detects the failure and automatically self heals which reduces downtime.
- Kubernetes helps to reduce costs by intelligently distributing workloads across multiple worker nodes in the cluster.
- Kubernetes provides a solution to help growing organisations manage multiple containers with ease.
In this course, you've learnt that Kubernetes is a container orchestration system that helps manage and coordinate the deployment, scaling and operations of containers across a cluster of machines or nodes. It ensures your applications run smoothly across different environments by automating many aspects of application management. With this knowledge at hand, you are now equipped with the foundational knowledge to start exploring and using Kubernetes in your projects.
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