Debug School: PrashanthL

Kubernetes Day-3 Summary

PrashanthL — Wed, 18 Oct 2023 12:16:12 +0000

Today I learnt the following topics

Daemon Set
Job & CronJob
ConfigMap
Services
Ingress

Daemon Set
To ensure specific pod runs on all or subset of nodes within a cluster.
kubectl get ds

Job & CronJob
Job is onetime activity.
kubectl get jobs

ConfigMap
Stored in cluster, commands same.

Services
We call it as Service and not Load Balancer
Service = Network Load Balancer
Ingress = Application Load Balancer

kubectl create svc -

*Ingress *
Ingress is a way for enabling traffic. Also helps in routing.
Ingress means a rule. It is an API object.
Ingress controller is exposed with the load balancer.

Path Based
Name Based
TLS Based

Kubernetes Day-2 Summary

PrashanthL — Tue, 17 Oct 2023 11:57:11 +0000

Today I have learnt the following topics

Namespaces
Pod
Replica sets
Deployments

Kubectl api-resources

Logical separation are called Namespaces
Pod is created in Namespace, worker is created in cluster

Any object in Namespace is shown as True
Any object in cluster is shown as false

*Secret Formula - *
C - Create
R - Get, Describe
U - Edit, Apply
D - Delete

** More detail son Pod**
To be added here

Replica Set
To be added here

Deployment has 5 features
Replication, Controller, Versioning, Rollout, Rollback
Rolling update is the default

What is Pod?

PrashanthL — Mon, 16 Oct 2023 11:57:01 +0000

Pod can only be instantiated and can not be created
Pod is running as long as container is running.
Pid-1 is running container, kill it container is killed
Node can have multiple pods
Static pod - there are 4 static pods - not controlled by K8s
System pod also known as static pod
User pod - dynamic pod contains applications
Pod life cycle - Pending, Running, Succeeded/failed which depends on container state
1 pod, 1 container is a good design
There are single container pod and multiple container pods

Kubernetes Assignment-1

PrashanthL — Mon, 16 Oct 2023 07:20:00 +0000

1. What is Kubernetes?

It is shortened as K8s. It is open-source container orchestration system for automating application deployment, scaling, management.
It is written in Go language.

2. Why do we need Kubernetes?

Need for running application without downtime
Better resource utilization
Auto Scaling applications based on demand

3. How Kubernetes works?
Has master and worker nodes
master has 4 components -

APIServer - worker node and the workstation can talk only through the api server
Cluster Store -
Controller Manager - core component delegates work to each node
Scheduler - responsible for scheduling containers onto nodes based on available resources and other factors.

Nodes: Nodes are the worker machines that run containerized applications. Each node has several components:

kubelet: The kubelet is responsible for managing the containers running on the node.
Container Runtime: The container runtime is responsible for running containers.
Kube-proxy: Kube-proxy is a network proxy that runs on each node and is responsible for implementing Kubernetes services and network policies.

What is a Pod?
A Pod is the smallest and simplest unit in the cluster