Can you explain the concept and main principles of installing and configuring Kubernetes on your own, without using managed solutions?

Setting up and configuring Kubernetes without managed solutions requires an understanding of the cluster architecture and components. The main steps:

1. Infrastructure preparation: you need to have several servers (virtual or physical) for the master and workers.

2. Installing Kubernetes components:

   • etcd — a distributed configuration store.
   • kube-apiserver — the API server for cluster interaction.
   • kube-controller-manager — controllers for managing state.
   • kube-scheduler — the task scheduler.
   • kubelet — an agent on each node to run containers.
   • kube-proxy — a network proxy for routing.

3. Network setup: installing a network plugin (e.g., Calico, Flannel) to ensure communication between pods.

4. Cluster initialization: using kubeadm init or manually, if not using tools.

5. Adding workers: connecting worker nodes to the master.

6. Configuring RBAC and security: creating roles and access policies.

7. Deploying applications: via YAML manifests.

It is important to understand that manual installation requires deep knowledge of Linux, networks, containerization, and Kubernetes. Tools like kubeadm are usually used, but each component can also be configured manually.