1. Pods
1.1. A Kubernetes abstration that represents a group or more application containers and some shared resources for those containers.
2. Service
2.1. Describes a logical set of pods
2.2. a policiy for accessing the pod se
2.3. types
2.3.1. ClusterIP
2.3.1.1. This default types exposes the service on a cluster-internal IP.
2.3.1.2. You can reach the service only from within the cluster
2.3.2. NodePort
2.3.2.1. This type of service exposes the service on each node's IP at a static port
2.3.3. LoadBalancer
2.3.3.1. This service type exposes the service externally using the load balancer of your cloud provider
3. Configuration
3.1. ConfigMap
3.2. Pods consume ConfigMaps as
3.2.1. Environmental Variables
3.2.2. command-line arguments
3.2.3. configuration files in a volume directory
4. Cluster
4.1. Is a set of node machines for running containerized applications
4.2. At a minimum, a cluster contains a master node and a worker node
4.3. Run on physical and virtual hardware
5. Nodes
5.1. Two Types
5.1.1. Master
5.1.2. Workers
5.2. A node is a worker machine in Kubernetes, previously known as a minion
5.3. Each node contains the process neccessary to run pods and is managed by the master components
5.4. The process on a node include the container runtime, kubelet and kube-proxy
6. Diagram
7. Kubernetes Control Plane
7.1. Worker Node Components
7.1.1. Components which run on worker and master nodes
7.1.2. kubelet - agent to ensure containers are running in pods
7.1.3. kube-proxy - allows network communication to pods
7.1.4. Container Runtime (docker) - runs on both master and work nodes
7.2. Master Node Components
7.2.1. Components which run on master node only
7.2.2. kube-apiserver - heart of the control plane, it controls everything
7.2.3. kube-scheduler - determines node placement for pods
7.2.4. kube-controller-manager - monitors state of resources (node, pods)
7.2.5. etcd - data store, runs only on the master nod, determines the # of master node instances
7.3. Version Control
7.3.1. CSP-AWS/EKS supports 3 most recent minor version of Kubernetes
7.3.1.1. Driver of cluster maintenance activities
7.3.2. kubectl version must be +1 thru -1 of kube-apiserver version
7.3.2.1. Driver of eksconnect maintenance
7.3.2.2. you should be aware and update regularly