kubectl
- This is a command-line utility which we would be using to interact with k8s cluster.
- This utility creates api-request internally and forwards them to kube-api server
- Refer Here for kubectl cheat sheet.
Kubernetes Objects
- k8s objects are persistent entities in the k8s system.
- These objects are used to represent the state of your cluster
- Every k8s object has
- Specification: This is also referred as object Spec
- Status: This is also referred as object status
- How can we describe a k8s object (Specification):
- K8s objects can be describe in the json format using k8s rest api or in yaml format via kubectl
- For api version Refer Here
K8s Pods
- Pods are the atomic unit of computing that you create in k8s
- A pod represents an application/microservice running in k8s cluster.
- Pods will have containers in it.
- Each container within a pod runs its own cgroup, but they share number of Linux namespaces like net, mnt etc.
- In k8s to create any object we have two ways
- imperative:
- We can create objects by executing commands Refer Here
- declarative:
- We create an object specification in a yaml file.
- Send/apply this yaml which has a specification & k8s master will do the rest to create/maintain the specification sent
- To create this specification we will be using k8s api reference
- imperative:
- Refer Here for the sample pod created
- To be effecient with k8s workflow
- We need to understand k8s objects
- we need to understand expressing object spec in yaml
- we need to be able read the status from k8s cluster
- Expectation:
- Configure kubectl
- Bookmark kubectl cheat
- create sample pod & delete it in k8s cluster.
