[AWS] AWS

The AWS Command Line Interface (AWS CLI) is a command-line tool that allows you to interact with AWS services using commands in your terminal/command prompt.

AWS CLI enables you to run commands to provision, configure, list, delete resources in the AWS cloud. Before you run any of the aws commands, you need to follow three steps:

1. Install AWS CLI
2. Create an IAM user with Administrator permissions
3. Configure the AWS CLI

Step 1. Install AWS CLI v2

Refer to the official AWS instructions to install/update AWS CLI (version 2) based on your underlying OS. You can verify the installation using the following command in your terminal (macOS)/cmd (Windows).

# Display the folder that contains the symlink to the aws cli tool
which aws
# See the current version
aws --version

See the sample output below. Note that the exact version of AWS CLI and Python may vary in your system.

Step 2. Create an IAM user

In this step, you will create an IAM user with Administrator permissions who is allowed to perform any action in your AWS account, only through CLI. After creating such an IAM user, we will use its Access key (long-term credentials) to configure the AWS CLI locally.

Let’s create an AWS IAM user, and copy its Access key.

AWS Identity and Access Management (IAM) service allows you to authorize users / applications (such as AWS CLI) to access AWS resources.

The Access key is a combination of an Access Key ID and a Secret Access Key. Let's see the steps to create an IAM user, and generate its Access key.

• Navigate to the IAM Dashboard, and create an IAM user.

• Set the user details, such as the name, and access type as Programmatic access only.

• Set the permissions to the new user by attaching the AWS Managed AdministratorAccess policy from the list of existing policies.

• Provide tags [optional], review the details of the new user, and finally create the new user.

• After a user is created successfully, download the access key file (.csv) containing the Access Key ID and a Secret Access Key. You can even copy the keys and stay on the same page. Don’t skip this step as this will be your only opportunity to download the secret access key file.

Step 3. Configure the AWS CLI

You will need to configure the following four items on your local machine before you can interact with any of the AWS services:

1. Access key - It is a combination of an Access Key ID and a Secret Access Key. Together, they are referred to as Access key. You can generate an Access key from the AWS IAM service, and specify the level of permissions (authorization) with the help of IAM Roles.
2. Default AWS Region - It specifies the AWS Region where you want to send your requests by default.
3. Default output format - It specifies how the results are formatted. It can either be a json, yaml, text, or a table.
4. Profile - A collection of settings is called a profile. The default profile name is default, however, you can create a new profile using the aws configure --profile new_name command. A sample command is given below.

If you have closed the web console that showed the access key, you can open the downloaded access key file (.csv) to copy the keys later. It should be something similar to:

AWSAccessKeyId=WANI9WATIG63GKCXA89VC74A
AWSSecretKey=kMT2Jn5NPkq1GxtoUqwUbgHtPbsf1ODm/Pbsf1OD

• Navigate to the home directory and check the current configuration:

  # Navigate to the home directory
  cd
  # View the current configuration
  aws configure list
  

• Set the default profile credentials

  aws configure --profile default
  

  The command above will store the access key in a default file ~/.aws/credentials and store the profile in the ~/.aws/config file. Upon prompt, paste the copied access key (access key id and secret access key). Enter the default region as us-east-1 and output format as json.

• Let the system know that your sensitive information is residing in the .aws folder

  export AWS_CONFIG_FILE=~/.aws/config
  export AWS_SHARED_CREDENTIALS_FILE=~/.aws/credentials
  

• After a successful credential set-up, your "credentials" file will look like:

• Windows users with GitBash only
  You will have to set the environment variables. Run the following commands in your GitBash terminal:

  setx AWS_ACCESS_KEY_ID AKIAIOSFODNN7EXAMPLE
  setx AWS_SECRET_ACCESS_KEY wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
  setx AWS_DEFAULT_REGION us-west-2
  

  Replace the access key ID and secret, as applicable to you. Windows users using WSL do not need this step, they will follow all steps as if they are Linux users.

Step 4. Run your first AWS CLI command

• Check the successful configuration of the AWS CLI, by running an AWS command:

  aws iam list-users
  

  The output will display the details of the recently created user:

  {
  "Users": [
      {
          "Path": "/",
          "UserName": "Admin",
          "UserId": "AIDAZMXYZ3LY2BNC5ZM5E",
          "Arn": "arn:aws:iam::388752792305:user/Admin",
          "CreateDate": "2021-01-28T13:44:15+00:00"
      }
  ]
  }
  

Troubleshoot

If you are facing issues while following the commands above, refer to the detailed instructions here -

1. Configuration basics
2. Configuration and credential file settings
3. Environment variables to configure the AWS CLI

Updating the specific variable in the configuration

In the future, you can set a single value, by using the command, such as:

# Syntax
# aws configure set <varname> <value> [--profile profile-name]
 aws configure set default.region us-east-2

It will update only the region variable in the existing default profile.