Intro Managment tool


K8S Managment Tools

There is a variety of management tools available for kuberntes. These tools interface with kuberntes to provide additional functionality. When using kubernetes, it is a good idea to be aware of some of these tools. 


 What is kubectl ?


Kubectl is the official command line interface for kubernetes. it is the main method we will use to work with kuberntes in this course. 

Syntax

kubectl [command] [TYPE] [NAME] [flags]

where command, TYPE, NAME, and flags are:

  • command: Specifies the operation that you want to perform on one or more resources, for example create, get, describe, delete.

  • TYPE: Specifies the resource type. Resource types are case-insensitive and you can specify the singular, plural, or abbreviated forms. For example, the following commands produce the same output:

    kubectl get pod pod1
kubectl get pods pod1
kubectl get po pod1

  • NAME: Specifies the name of the resource. Names are case-sensitive. If the name is omitted, details for all resources are displayed, for example kubectl get pods.

    When performing an operation on multiple resources, you can specify each resource by type and name or specify one or more files:

    • To specify resources by type and name:

      • To group resources if they are all the same type: TYPE1 name1 name2 name<#>.
        Example: kubectl get pod example-pod1 example-pod2

      • To specify multiple resource types individually: TYPE1/name1 TYPE1/name2 TYPE2/name3 TYPE<#>/name<#>.
        Example: kubectl get pod/example-pod1 replicationcontroller/example-rc1

    • To specify resources with one or more files: -f file1 -f file2 -f file<#>

      • Use YAML rather than JSON since YAML tends to be more user-friendly, especially for configuration files.
        Example: kubectl get -f ./pod.yaml

  • flags: Specifies optional flags. For example, you can use the -s or --server flags to specify the address and port of the Kubernetes API server.

What is kubeadm ?

We have already used kubeadm, which is a tool for quickly and easily creating kubenetes clusters.

Kubeadm is a tool built to provide kubeadm init and kubeadm join as best-practice "fast paths" for creating Kubernetes clusters.

kubeadm performs the actions necessary to get a minimum viable cluster up and running. By design, it cares only about bootstrapping, not about provisioning machines.


What is Minikube ?

Minikube allows us to automatically set up a local single-node kubernets cluster. It is great for getting kuberntes up and running quickly for development purpose. 


What is Helm ?


Helm provides templating and package management for kuberntes objects. we can use it to manage our own templates (known as charts). We can also download and use shared templates. 

Helm is a tool to help you define, install, and upgrade applications running on Kubernetes. At its most basic, Helm is a templating engine that creates Kubernetes manifests. What makes Helm more than that is it can upgrade and scale applications as well.


What is Kompose ?

kompose helps us translate docker compose files into kubernetes objects. if we are using docker compose for some part of our workflow, we can move our application to kuberntes easily with kompose. 


What is Kustomize ?

Kustomize is a configuration management tool for managing kubernetes object configurations. It allows us to share and re-use templated configurations for kubernetes applications. 


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