Introduction to Kubernetes (notes 1).

Course:
https://cloudacademy.com/course/introduction-to-kubernetes/introduction/?context_id=92&context_resource=lp

Kubernetes is a container orchestration tool.

• Clusters: refers to all of the machines collectively and can be thought of as the entire running system.
• Nodes are the machines in the cluster.
• Nodes are categorized as workers or masters
• Worker nodes include software to run containers managed by the Kubernetes control plane.
• Master nodes run the control plane
• The control plane is a set of APIs and software that Kubernetes users interact with.
• The APIs and software are referred to as master components

Scheduling:

• Control plane schedules containers onto nodes.
• Scheduling decisions consider required CPU and other factors.
• Scheduling refers to the decision process of placing containers onto nodes.

Kubernets Pods:
**- Containers are grouped onto pods.

• Pods can include one or more containers.
• All containers in a pod run on the same node.
• Pods are the smallest building block in Kubernetes

Services:

• Services define networking rules for exposing groups of Pods

  • To other pods
  • To the public Internet

• Use labels to select a group of Pods.

• Service has a fixed IP address.

• Distribute requests across Pods in the group.

Kubernetes Deployments:
Manage deploying configuration changes to running Pods.

Pods:

• Pods are Kubernetes' basic building block
• Declare Pods and other resources in manifest files
• metadata includes name and labels
• Pod spec include container names, images
• Containers communicate over localhost within a Pod
• kubectl logs

• logs record what's written to standard output and standard error

• Horizontal scaling.