Debug School: ASHISH KUMAR AWASTHI

Assignment-DAY3

ASHISH KUMAR AWASTHI — Mon, 25 Sep 2023 07:46:20 +0000

What is service?
Services are endpoint which is used to create load balancing for pods. Different label used in load balancing .This label must match to the pod label as well load balance label in order to get proper load balancing.

Why we need it?
Services usually create load balancing at multiple Laval ie Pod level (front and beckend) or node level.
Three type of service available:
1) ClusterIP
2) Node Port
3) Load balancer

How it works?
First load balancer at pod level exposed the front end Pod port which is known as Cluster IP load balancing.
Node port usually load balancer at Node port, which exposed the front end Pod level port to externally at Node level.
It may needed to create load balancer externally at cloud end, to access container from outside world. This may be done with the help of DNS.

Command for it
Create two pod:--
vi pod5.yaml
vi pod6.yaml
kubectl apply -f pod5.yaml
kubectl apply -f pod6.yaml

Create ClusterIP node balancer:-

kubectl create service clusterip ash-cs --tcp=5678:80
kubectl describe svc ash-cs
kubectl get pods --show-labels
!!--Modify the lable at Service ash-cs that must match to the pods.
kubectl edit svc ash-cs

!!--Create Node Port load Balancer:--
kubectl create service nodeport ash-ns --tcp=5678:80
kubectl get pods --show-labels

!!--Modify the Label as per the pod lable:--
kubectl edit svc ash-ns

kubectl describe svc ash-ns
kubectl describe svc ash-cs

Check the access using mapped port and IP of Cluster and Node IP
curl http://10.111.228.235:5678
curl http://10.100.232.215:5678
watch curl http://10.111.228.235:5678

Assignment Day-2

ASHISH KUMAR AWASTHI — Fri, 22 Sep 2023 12:07:01 +0000

What is Namespaces? Explain with Image
Namespace is the grouping inside the cluster, which can be created based on name, tag, resources etc. Each pod can be assigned to this group and can create logical grouping of pods.
Such as namespace can be created based on memory resource or administrative tag. Pod can be assigned to these namespace which can be used limited memory assigned to the namespace or only administrator can access the pod.

What is Pod? Explain with Image
Pod is logical grouping. Its basic atomic unit. Pod may consist one or many container. Pod shares the resources of node.Pods can only be instantiated. Pods can be created using yaml.
Pod created by scheduler on the request of worker node.
Kubeproxy assign IP on newly created pod.

What is ReplicaSets? Explain with Image
Replicasets used to scale the pod. Using ReplicaSet one can create or remove large no of pod within a second.Replica set useful to rollout or rollback pods.
Replicaset has two part:
1) Controller
2) Replication

What is Deployment? Explain with Image
Deployment use to create or remove or replace large no of pod.It is usefull in production when large no of pod need to replace by any reason such as updated software, version control etc.
It has below component
1) versioning
2) Replication
3) Controlling
4) Rollout
5) Roll Back

What is Kubernetes?

ASHISH KUMAR AWASTHI — Thu, 21 Sep 2023 09:03:18 +0000

Kubernetes is management platform which controls and manages container. Kubernetes resolve the problem which usually encountered in Docker like scalability, Load balancing, Self heal etc