AWS · zero to on-call
The cloud, without
the surprise bill.
IAM, networking, compute and storage, and the cost traps, practised on a simulated account that never touches a real one.
Learning AWS?
Start from zero, step by step.
Levels in order, each with a hands-on incident to fix on a simulated account.
Something broken right now?
Paste the error, get the fix.
The cause, the commands to confirm it and the fix, for every common AWS error.
Everything you need, from the first command to the 3 a.m. incident.
A simulated account.
AccessDenied, unreachable instances, public buckets and runaway costs, with the real aws CLI and real error messages.
IAM, read aloud.
Paste a policy: what it really allows, statement by statement, and what is risky.
Exam-style, explained.
Every answer comes with the reasoning.
Region to subnet.
Every component, how it fails.
Learn why it happens, then practise the fix.
Fix a broken AWS account. Right here.
A simulation: real aws CLI commands and real error messages, over a modelled account. Nothing reaches AWS and nothing costs money.
Practise on a real account, safely
A sandbox with a budget
Use a separate account for labs, sign in with IAM Identity Center, and set a budget alert before you create anything.
# 1. Sign in (once per day)
aws configure sso
aws sso login --profile sandbox
# 2. Check where you are
aws sts get-caller-identity --profile sandbox
# 3. Get the course
git clone https://github.com/SandeepKomal/AWS.git
Clean up when you are done
NAT gateways, load balancers, Elastic IPs, databases and volumes bill by the hour. Delete stacks, then check nothing is left.
aws cloudformation delete-stack --stack-name lab-vpc
aws ec2 describe-nat-gateways --query 'NatGateways[?State==`available`]'
aws ec2 describe-addresses
aws ec2 describe-volumes --filters Name=status,Values=available
Prices: AWS pricing · AWS Pricing Calculator · Security checklist
Your path
Progress is saved in this browser only. Tick a level when you have done its lab.
Quiz
Exam-style questions for every level, with the reasoning for every answer, which is where the learning is.
Policy X-ray
Paste an IAM policy, a role trust policy, an S3 bucket policy or a KMS key policy. Every statement is explained in plain words, and risky patterns are flagged.
Stuck on an error?
Paste the error message, or pick a symptom. Each answer explains why it happens, how to confirm it and how to fix and prevent it, then gives you a safe scenario to break and fix it yourself, so you recognise it next time.
A plain list of every problem, readable without JavaScript: problems.html.
Cheat sheet
The aws CLI commands people use every day. Try runs a command in the playground, in the scenario it needs. Lab marks the ones that need a real account.
Fill in your own names
AWS architecture
A typical web application on AWS, from a customer's request to the database. Point at a component, or tab to it, to read what it does and how it fails.