Debug School: Sachin Pargi

What is POD, write a 10 lines explaination on POD by Sachin Pargi

Sachin Pargi — Thu, 20 Oct 2022 06:09:21 +0000

Pod is a unit of execution on kubernetes cluster
Pod is a label assigned to group of containers
Pod is instantiated by the kubelet.
Pods communicate over pod network
Pod consists of group of containers
Pod has an ip address.
Pod is a way to assign network and storage resources.
All containers share the same ip in the pod.

Architecture of Kubernetes and few lines for each component by Sachin Pargi

Sachin Pargi — Thu, 20 Oct 2022 06:05:58 +0000

Kubernetes cluster consists of master nodes and worker nodes. Multiple master nodes are needed for high availability and there can be n number of nodes. It allows to run thousands of pods at scale
Master node has 4 components
1) API server - Exposes many APIs for each type of functionality and consumes json files.
2) Cluster store - stores the json manifest along with other data in persistent store. etcd is used for storing data. There are many instances of it for high availability.
3) Controller - Controller runs in a loop. Think this like many scripts. Each script checks specific activity - like namespace checks, node checks,
4) Scheduler - schedules and manages the pods on many worker nodes using kubelet on the worker nodes.

Worker nodes consists of 3 components
1) kubelet - responsible for instantiating the pod
2) kube-proxy - responsible for reflecting the calls to the right pod/container
3) container engine - docker or rocker

What are the 10 feature which we need at prod level, Kubernetes has by it by Sachin Pargi

Sachin Pargi — Thu, 20 Oct 2022 05:59:34 +0000

1) node management
2) ip management
3) load balancer
4) restart of applications
5) replica management
6) network policies
7) monitoring of applications
8) storage policies
9) logging management
10) desired state of applications

What is Kubernetes by Sachin Pargi

Sachin Pargi — Thu, 20 Oct 2022 05:56:09 +0000

It is a cluster management framework which allows datacenter to be viewed as a single computer, thereby allowing easy orchestration and management of workloads at scale.