AWS CLI and CloudShell

While the Management Console is great for exploration and visual tasks, the AWS Command Line Interface (CLI) is essential for automation, scripting, and efficient day-to-day operations. AWS CloudShell gives you a browser-based terminal with the CLI pre-installed, so you can start running commands without any local setup.

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What Is the AWS CLI?

The AWS CLI is a unified command-line tool that lets you interact with AWS services by typing commands in a terminal. Anything you can do in the console, you can do with the CLI — and more.

Why Use the CLI?

Benefit	Explanation
Speed	A single command can replace multiple console clicks
Scripting	Chain commands in Bash, PowerShell, or Python scripts
Automation	Integrate with CI/CD pipelines and cron jobs
Reproducibility	Save commands in version-controlled scripts
Bulk operations	Operate on hundreds of resources with loops and filters

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Installing the AWS CLI

The CLI is available for macOS, Linux, and Windows.

macOS

# Download and install the latest version
curl "https://awscli.amazonaws.com/AWSCLIV2.pkg" -o "AWSCLIV2.pkg"
sudo installer -pkg AWSCLIV2.pkg -target /

Linux

curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip"
unzip awscliv2.zip
sudo ./aws/install

Windows

Download the MSI installer from https://awscli.amazonaws.com/AWSCLIV2.msi and run it.

Verify Installation

aws --version
# aws-cli/2.x.x Python/3.x.x Darwin/23.x.x source/arm64

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Configuring the AWS CLI

Before you can use the CLI, you need to provide your credentials and default settings.

Quick Configuration

aws configure

This prompts for four values:

Setting	Example	Description
Access Key ID	AKIAIOSFODNN7EXAMPLE	From your IAM user's security credentials
Secret Access Key	wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY	Paired with the access key
Default Region	eu-west-2	The Region commands will target by default
Output Format	json	json, text, table, or yaml

Credentials are stored in ~/.aws/credentials and settings in ~/.aws/config.

Named Profiles

You can configure multiple profiles for different accounts or roles:

aws configure --profile production
aws configure --profile development

Then specify which profile to use:

aws s3 ls --profile production

Or set an environment variable:

export AWS_PROFILE=production
aws s3 ls  # uses the production profile

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CLI Command Structure

Every AWS CLI command follows this pattern:

aws <service> <action> [options]

Examples

# List all S3 buckets
aws s3 ls

# Describe all EC2 instances
aws ec2 describe-instances

# Create a DynamoDB table
aws dynamodb create-table \
  --table-name Users \
  --attribute-definitions AttributeName=UserId,AttributeType=S \
  --key-schema AttributeName=UserId,KeyType=HASH \
  --billing-mode PAY_PER_REQUEST

# Get the caller identity (who am I?)
aws sts get-caller-identity

Output Formatting

# JSON (default)
aws ec2 describe-instances --output json

# Human-readable table
aws ec2 describe-instances --output table

# Tab-separated text (great for scripting)
aws ec2 describe-instances --output text

# YAML
aws ec2 describe-instances --output yaml

Filtering with --query

The --query parameter uses JMESPath syntax to filter and shape output:

# Get just the instance IDs
aws ec2 describe-instances \
  --query 'Reservations[*].Instances[*].InstanceId' \
  --output text

# Get instance ID and state
aws ec2 describe-instances \
  --query 'Reservations[*].Instances[*].[InstanceId,State.Name]' \
  --output table

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Common CLI Commands