Kubernetes

etcd is a process running on 202201291535’s #202202012056 that stores important cluster data such as the state of 202202012054. Those data will be updated once the cluster changes such as dead pop and request from the client.

Storage Class is a type of #202201311647 that could dynamically create a 202202151901 on demand. It is not under the control of 202201291535 cluster.

Red Hat Ansible Automation Platform provides 202204272021# automation, cloud services , and content in 202204300837# which includes infrastructure like 202204081225#, cloud or container technologies (202110201636# and 202201291535#), network (CISCO) and security including devices and how they fit in the environment.

Persistent Volume Claim is a type of #202201311647 that help #202201311630 to secure necessary #202202151901. It is under the control of 202201291535 cluster.

Persistent Volume is a type of #202201311647 that hold an actual storage. It will not be under the control of 202201291535 cluster. For it to be effective, it needs to be declared beforehand the 202201311630 that will use it.

Minikube is a tool to create a local #202201291535 cluster where all of the components are running in the same node including the 202202012056 and 202202012054.

A usual worker node in #202201291535 contains a minimal of three processes:

Volume is a component from #202201291535 that could attach local or remote storage to a #202201311630. It can ensure data persistency especially when used alongside with databases.

StatefulSet is a component from #202201291535 that define a blueprint and build up abstraction for stateful #202201311630 replication. It is usually used for database construction. For stateless pod see 202201311650.

Service is a component from #202201291535 that help #202201311630 to fixate a permanent 202206151453#. It also act as a load balancer between nodes.

Secret is a component from #202201291535 that could store environment variables or user credentials such as username and password. They should be encoded in base64. However, the built-in security mechanism is not enabled by default.

Scheduler is a process running on 202201291535’s #202202012056 that decides which 202202012054 should the new #202201311630 be allocated. The data from the 202202012234 such as the required resources that the pod needed and the currently available resources in the node will affect the dicision made by the scheduler.

Pod is the smallest #202201291535 unit which provides the abstraction over the containers inside it. If a pod dies, Kubernetes will restart it with a new state.

A #202201291535 cluster usually contains two kind of nodes:

Namespace is useful in grouping different #202201291535 components except for 202201311634# and globally accessible components such as 202201311647# and 202202111433#.

Master Node in #202201291535 plays a role in managing multiple 202202012054#. It contains at least four proccesses:

Ingress is a component from #202201291535 that assign domain name to 202201311634#. It will be managed by Ingress Controller 202201311630.

Deployment is a component from #202201291535 that define a blueprint and build up abstraction for stateless #202201311630 replication. For stateful pod see 202201311654.

Controller Manager is a process running on 202201291535’s #202202012056 that notifies 202202012216 when there is a change of cluster status. This is particularly useful in rescheduling dead pods.

ConfigMap is a component from #202201291535 that contain the external configuration for the containarised application in a #202201311630. User credentials such as username and password could be store in this component but a better way to do this is to store them at 202201311645#.

API Server is a process running on 202201291535’s #202202012056 that manages and authenticates client’s requests.

Kubelet is a proccess running on 202201291535’s #202202012054 that assigns node’s resources to the container pods inside the node.

kubens is a #202201291535 tool for changing the active #202202111425.

Kubectl is a CLI tool to interact with the #202201291535’s #202202012124. This includes the cloud cluster and 202202032024.

Kube Proxy is a process running on 202201291535’s #202202012054 that forwards the requests from #202201311634 to 202201311630.