How Does a Kubernetes Cluster Work?

Let's take a simple example.

Suppose you want to run a web application with three replicas.

You define the desired state:

replicas: 3

Then you submit the configuration to Kubernetes.

Something like:

kubectl apply -f deployment.yaml

The flow is roughly:

Developer
    |
    v
kubectl
    |
    v
API Server
    |
    v
Scheduler / Controllers
    |
    v
Worker Node
    |
    v
Pod
    |
    v
Container

• The scheduler decides where the Pod should run.
• The kubelet on that node makes sure the Pod is running.
• The controllers continue watching the state of the cluster.
• If something changes, Kubernetes works to move the actual state back toward the desired state.

npm ERR! No versions available

 C:\Users\mohammadr>npm install gatsby-source-aem

npm notice

npm notice New major version of npm available! 8.19.2 -> 9.2.0

npm notice Changelog: https://github.com/npm/cli/releases/tag/v9.2.0

npm notice Run npm install -g npm@9.2.0 to update!

npm notice

npm ERR! code ENOVERSIONS

npm ERR! No versions available for gatsby-source-aem

npm ERR! A complete log of this run can be found in:

npm ERR!     C:\Users\mohammadr\AppData\Local\npm-cache\_logs\2023-01-04T08_05_41_116Z-debug-0.log

Cannot find module 'aws-sdk'

 

Error: Cannot find module 'aws-sdk'
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:636:15)
    at Function.Module._load (internal/modules/cjs/loader.js:562:25)
    at Module.require (internal/modules/cjs/loader.js:692:17)
    at require (internal/modules/cjs/helpers.js:25:18)
    at Object.<anonymous> (E:\assignment\DynamoDBtoCSV\dynamoDBtoCSV.js:2:13)
    at Module._compile (internal/modules/cjs/loader.js:778:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)
    at Module.load (internal/modules/cjs/loader.js:653:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
    at Function.Module._load (internal/modules/cjs/loader.js:585:3)

How to fix cannot find module aws-sdk error?

To install the aws-sdk module you need to run the below npm install command.

npm install aws-sdk

OR 

npm install aws-sdk --save

After executing the above command, the Node aws-sdk module will get downloaded and save locally in the machine. Below is the snapshot of successful execution.

E:\assignment\DynamoDBtoCSV>npm install aws-sdk --save
+ aws-sdk@2.771.0
added 14 packages from 66 contributors and audited 15 packages in 62.496s
found 0 vulnerabilities