Other Kubernetes

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kubectl get po -A
kubectl cluster-info

List deployments

kubectl get deployments.apps kubectl get deployment NAME -o yaml

• A "pod" is an abstraction of K8s of a Docker container.
• A "deployment" is a blueprint for a "pod" and we can tell k8s how many of the same pod we would like to have.
• "Service" public port mapped to a pod, communication between pods, load balancer for pod replications
• Database cannot be replicated by a "Service" because they have state.
• "StatefulSet"
• "Ingress" to handle the requests from the external world
• "ConfigMap"
• "Volumes" - to store persistent data

On each node there are 3 processes:

• container runtime (Docker)
• Kubelet (interacts with both the container runtime and the machine itself)
• KubeProxy forwards the requests

On the Master process has 4 processes:

• API Server (cluster gateway) act as a gatekeeper for authentication
• Scheduler - decide where to run the next pod based on the available resources (then tells the Kublet on the node to run the pod)
• Controller Manager
• etcd - a key-value store, the brain of the cluster

A Kubernetes cluster can have several master nodes.