AWS Credentials: What They Are and Why They Matter

When you work with Amazon Web Services, AWS credentials are the keys that let you access resources such as EC2 instances, S3 buckets, and Lambda functions. They consist of an access key ID and a secret access key, and optionally a session token for temporary credentials. Understanding how these credentials are created, stored, and rotated is essential for keeping your cloud environment secure.

How to Get AWS Credentials

There are several ways to obtain AWS credentials, each suited to a different use case. The most common methods are:

  1. IAM Users – Create an IAM user in the AWS Management Console, then generate an access key pair. This is the standard approach for long‑term programmatic access.
  2. IAM Roles with Temporary Security Tokens – Use AWS STS (Security Token Service) to assume a role and receive short‑lived credentials. This method is recommended for applications running on EC2, ECS, or Lambda.
  3. Single Sign‑On (SSO) – Configure AWS SSO or an external identity provider (IdP) and retrieve credentials via the AWS CLI or SDKs.

In the official AWS documentation, the How to Get section walks you through each step, from creating a policy to attaching it to a user or role.

Managing AWS Credentials with IAM

IAM (Identity and Access Management) is the foundational service for controlling who can do what in your AWS account. In this episode, Eoin and Luciano talk about how to manage credentials at scale, emphasizing the importance of the principle of least privilege.

Creating Policies for Credential Use

When you define an IAM policy, you specify actions (e.g., s3:ListBucket) and resources (e.g., arn:aws:s3:::my-bucket/*). Attach the policy to a user, group, or role to limit the scope of the generated credentials.

Rotating Credentials Regularly

Rotation reduces the risk of compromised keys. A typical rotation workflow includes:

Automated scripts can be scheduled with AWS Lambda to enforce rotation every 90 days, aligning with security best practices.

How to Set Up Credentials in Your Development Environment

In this video I teach you about how to set up the AWS CLI so you can test your credentials locally. Follow these steps:

  1. Install the AWS CLI (version 2 is recommended).
  2. Run aws configure and enter your access key ID, secret access key, default region, and output format.