Debug School: Subbarao

Day3: Assignment #1-subba

Subbarao — Wed, 18 Oct 2023 12:11:50 +0000

what are the ways to deploy pod? pod Replication controller Replica set deployment Daemon sets stateful sets

Daemon sets: min and max one pod per node. example for this canal
canal is netwrok plugin for proxy.
similarly we have kube-proxy which acts eternet/bridge.

what is job and cronjob
job we can define the container and it will go off once it is done.
cronjob, we can define the job at regular intervals
config map
this is configurations required for service and we can use in service as volume mounts.
its stored in etcd i.e. as key and value pair
load balancer
we have n/w load balancer and application load balancer
application load balancer example is ingress.

there were 4 service types
clustered ip
external name
load balancer
nodeport

with clusteredip we can create load balancer but we need match the selector label

Nodeport will create service of type clusteredtype and will make service available to all hosts

loadbalancer: it is ahead of the cluster and we can redirect to service and then load balancer and to nodes

Ingress: to manage application well we will have to use ingress which is outside of kubernetes and it balances the load
3types are there in ingress

path based
Name based
TLS Based

Day 2: Assignment #1: Subba

Subbarao — Tue, 17 Oct 2023 05:18:41 +0000

1. what is Namespace?

Answer: A namespace provides scope for Kubernetes resources. it is useful when many users across multiple teams or projects use the same cluster. it is logical separation in a cluster. we can restrict access the one namespace to other. ALso we can restrict access the pods inside namespace. by default it is default name space if we wont provide any namespace.

Assignment #2: Pod- Subbarao

Subbarao — Mon, 16 Oct 2023 11:50:46 +0000

1. what is POD?

Answer: POD is logical entity of container. pod contains many containers. All containers in pod share single IP but different ports. pod lifecycle contains different stages i.e. pending, running, failed. To make pod work we need to have Yaml files and that is declarative model and mention about requirement in yaml file.
the phase of pod goes from VM->container->POD
Pod spread across both master node and worker node. To get all pods we need to use
kubectl get pods command.
pod has different combinations like
1 pod with single conatainer
1 pod with multiple containers
1 pod with 1 worker
multiple pods with 1 worker.

Assignment #1: Subbarao

Subbarao — Mon, 16 Oct 2023 07:22:14 +0000

1. what is kubernetes?

Answer: Kubernetes also referred as k8s, it is an open source platform. It manages the containers across private, public, hybrid environments. we can manage microservice architecture to manage with kubernetes. we can do container orchestration with kubenetes. it was originated from borg->omega->kubernetes.

2. why do you need kubernetes?

Answer: One of the benefits of Kubernetes is that it makes building and running complex applications much simpler. Standard services like local DNS and basic load-balancing that most applications need are easy to use. The pods that wrap around containers are easy to build configurations. One single API much easier to create applications that manage other applications. Developers can concentrate on the applications rather than focusing on build and manage.

3. How kubernets works?

Answer: kubernetes works as master-workernode architecure. In the Master node we have 4 components
(a)Kube-apiserver: it is the front end to the control panel and it consumes json.
(b)Cluster store: it is persistence data that means the data stores in Database.
etcd is the database was used in cluster store and its kind of mongoDB.
(c)Kube-controller-manager:
Here we have different types of controllers like

Node controller
Endpoints controller
Namespace controller All interacts with API server and informs the each controller status (d)Kube-scheduler: it watches apiserver for new pods. its consists of affinity/anti-affinity,constraints,resources.

kubectl controlls master server.

In the worker node
we have Kubelet, container engine, kube-proxy.
kubelet: the main kubernetes agent registers node with clsuter watches apiserver instantiates pods reports back to master exposes endpoint on 10255
container engine: which manages all the containers in pods.
pod is logical entity
kube-proxy: all containers in pod gets single IP.

4. Exaplin kubernetes architecure?

Kubernetes architecture, also sometimes called Kubernetes application deployment architecture or Kubernetes client server architecture, is used to compose, scale, deploy, and manage application containers across host clusters.