AWS IAM Best Practices

1. Introduction

AWS Identity and Access Management (IAM) is a web service that helps you securely control access to AWS services and resources for your users. This lesson covers best practices to ensure secure management of permissions and user access.

2. Key Concepts

2.1 IAM Users

An IAM user is an entity that you create in AWS to represent a person or application that interacts with AWS resources.

2.2 IAM Roles

IAM roles are similar to users but are intended to be assumed by anyone who needs them, including AWS services and applications.

2.3 Policies

Policies define permissions and determine what actions are allowed on resources. They can be attached to users, groups, or roles.

3. IAM Best Practices

Use least privilege principles when assigning permissions.
Regularly review IAM policies and user permissions.
Enable MFA (Multi-Factor Authentication) for all users.
Utilize IAM roles instead of IAM users when possible.
Implement access keys rotation and avoid hardcoding them in applications.
Use service control policies for organizations to manage permissions across multiple AWS accounts.
Enforce password policies for IAM users.
Monitor and log IAM activity using AWS CloudTrail.

Note: Regular audits of IAM settings are crucial to maintain security over time.

4. Code Examples

Below is an example of how to create an IAM user with the AWS CLI.


aws iam create-user --user-name NewUser
aws iam attach-user-policy --user-name NewUser --policy-arn arn:aws:iam::aws:policy/AmazonS3ReadOnlyAccess

5. FAQ

What is the least privilege principle?

Least privilege means granting only the permissions necessary to perform a task, reducing the risk of unauthorized access.

How often should I rotate access keys?

Access keys should be rotated regularly, ideally every 90 days, and should be removed when no longer needed.

What is MFA and why is it important?

MFA adds an additional layer of security by requiring not only a password but also a second factor, such as a mobile app or hardware token.

6. Summary

Implementing IAM best practices is essential for maintaining a secure AWS environment. Follow the guidelines outlined in this lesson to enhance your security posture.