How to Access the AWS Management Console Using AWS Microsoft AD and Your On-Premises Credentials

AWS Directory Service for Microsoft Active Directory, also known as AWS Microsoft AD, is a managed Microsoft Active Directory (AD) hosted in the AWS Cloud. Now, AWS Microsoft AD makes it easy for you to give your users permission to manage AWS resources by using on-premises AD administrative tools. With AWS Microsoft AD, you can grant your on-premises users permissions to resources such as the AWS Management Console instead of adding AWS Identity and Access Management (IAM) user accounts or configuring AD Federation Services (AD FS) with Security Assertion Markup Language (SAML).

In this blog post, I show how to use AWS Microsoft AD to enable your on-premises AD users to sign in to the AWS Management Console with their on-premises AD user credentials to access and manage AWS resources through IAM roles.

Background

AWS customers use on-premises AD to administer user accounts, manage group memberships, and control access to on-premises resources. If you are like many AWS Microsoft AD customers, you also might want to enable your users to sign in to the AWS Management Console using on-premises AD credentials to manage AWS resources such as Amazon EC2, Amazon RDS, and Amazon S3.

Enabling such sign-in permissions has four key benefits:

1. Your on-premises AD group administrators can now manage access to AWS resources with standard AD administration tools instead of IAM.
2. Your users need to remember only one identity to sign in to AD and the AWS Management Console.
3. Because users sign in with their on-premises AD credentials, access to the AWS Management Console benefits from your AD-enforced password policies.
4. When you remove a user from AD, AWS Microsoft AD and IAM automatically revoke their access to AWS resources.

IAM roles provide a convenient way to define permissions to manage AWS resources. By using an AD trust between AWS Microsoft AD and your on-premises AD, you can assign your on-premises AD users and groups to IAM roles. This gives the assigned users and groups the IAM roles’ permissions to manage AWS resources. By assigning on-premises AD groups to IAM roles, you can now manage AWS access through standard AD administrative tools such as AD Users and Computers (ADUC).

After you assign your on-premises users or groups to IAM roles, your users can sign in to the AWS Management Console with their on-premises AD credentials. From there, they can select from a list of their assigned IAM roles. After they select a role, they can perform the management functions that you assigned to the IAM role.

In the rest of this post, I show you how to accomplish this in four steps:

1. Create an access URL.
2. Enable AWS Management Console access.
3. Assign on-premises users and groups to IAM roles.
4. Connect to the AWS Management Console.

Prerequisites

The instructions in this blog post require you to have the following components running:

• A Microsoft AD directory created in the AWS Cloud. To learn more, see Create a Microsoft AD Directory.
• Your existing on-premises Active Directory.
• A two-way forest trust relationship from AWS Microsoft AD to your on-premises Active Directory. To learn more, see Simplified Configuration of Trust Relationship in the AWS Directory Service Console. For additional information about trusts and to learn about domainless sign-in for AWS Management Console access, see How to Easily Log On to AWS Services by Using Your On-Premises Active Directory.
• IAM roles with trust relationships configured to AWS Directory Service. If you need help doing this, see Editing the Trust Relationship for an Existing Role

Note: You can assign IAM roles to user identities stored in AWS Microsoft AD. For this post, I focus on assigning IAM roles to user identities stored in your on-premises AD. This requires a forest trust relationship between your on-premises Active Directory and your AWS Microsoft AD directory.

Solution overview

For the purposes of this post, I am the administrator who manages both AD and IAM roles in my company. My company wants to enable all employees to use on-premises credentials to sign in to the AWS Management Console to access and manage their AWS resources. My company uses EC2, RDS, and S3. To manage administrative permissions to these resources, I created a role for each service that gives full access to the service. I named these roles EC2FullAccess, RDSFullAccess, and S3FullAccess.

My company has two teams with different responsibilities, and we manage users in AD security groups. Mary is a member of the DevOps security group and is responsible for creating and managing our RDS databases, running data collection applications on EC2, and archiving information in S3. John and Richard are members of the BIMgrs security group and use EC2 to run analytics programs against the database. Though John and Richard need access to the database and archived information, they do not need to operate those systems. They do need permission to administer their own EC2 instances.

To grant appropriate access to the AWS resources, I need to assign the BIMgrs security group in AD to the EC2FullAccess role in IAM, and I need to assign the DevOps group to all three roles (EC2FullAccess, RDSFullAccess, and S3FullAccess). Also, I want to make sure all our employees have adequate time to complete administrative actions after signing in to the AWS Management Console, so I increase the console session timeout from 60 minutes to 240 minutes (4 hours).

The following diagram illustrates the relationships between my company’s AD users and groups and my company’s AWS roles and services. The left side of the diagram represents my on-premises AD that contains users and groups. The right side represents the AWS Cloud that contains the AWS Management Console, AWS resources, IAM roles, and our AWS Microsoft AD directory connected to our on-premises AD via a forest trust relationship.

Let’s get started with the steps for this scenario. For this post, I have already created an AWS Microsoft AD directory and established a two-way forest trust from AWS Microsoft AD to my on-premises AD. To manage access to AWS resources, I have also created the following IAM roles:

• EC2FullAccess: Provides full access to EC2 and has the AmazonEC2FullAccess AWS managed policy attached.
• RDSFullAccess: Provides full access to RDS via the AWS Management Console and has the AmazonRDSFullAccess managed policy attached.
• S3FullAccess: Provides full access to S3 via the AWS Management Console and has the AmazonS3FullAccess managed policy attached.

To learn more about how to create IAM roles and attach managed policies, see Attaching Managed Policies.

Note: You must include a Directory Service trust policy on all roles that require access by users who sign in to the AWS Management Console using Microsoft AD. To learn more, see Editing the Trust Relationship for an Existing Role.

Step 1 – Create an access URL

The first step to enabling access to the AWS Management Console is to create a unique Access URL for your AWS Microsoft AD directory. An Access URL is a globally unique URL. AWS applications, such as the AWS Management Console, use the URL to connect to the AWS sign-in page that is linked to your AWS Microsoft AD directory. The Access URL does not provide any other access to your directory. To learn more about Access URLs, see Creating an Access URL.

Follow these steps to create an Access URL:

1. Navigate to the Directory Service Console and choose your AWS Microsoft AD Directory ID.
   
2. On the Directory Details page, choose the Apps & Services tab, type a unique access alias in the Access URL box, and then choose Create Access URL to create an Access URL for your directory.
   

Your directory Access URL should be in the following format: <access-alias>.awsapps.com. In this example, I am using https://example-corp.awsapps.com.

Step 2 – Enable AWS Management Console access

To allow users to sign in to AWS Management Console with their on-premises credentials, you must enable AWS Management Console access for your AWS Microsoft AD directory:

1. From the Directory Service console, choose your AWS Microsoft AD Directory ID. Choose the AWS Management Console link in the AWS apps & services section.
   
2. In the Enable AWS Management Console dialog box, choose Enable Access to enable console access for your directory.
   

This enables AWS Management Console access for your AWS Microsoft AD directory and provides you a URL that you can use to connect to the console. The URL is generated by appending “/console” to the end of the access URL that you created in Step 1: <access-alias>.awsapps.com/console. In this example, the AWS Management Console URL is https://example-corp.awsapps.com/console.

Step 3 – Assign on-premises users and groups to IAM roles

Before you users can use your Access URL to sign in to the AWS Management Console, you need to assign on-premises users or groups to IAM roles. This critical step enables you to control which AWS resources your on-premises users and groups can access from the AWS Management Console.

In my on-premises Active Directory, Mary is already a member of the DevOps group, and John and Richard are members of the BIMgrs group. I already set up the trust from AWS Microsoft AD to my on-premises AD, and I already created the EC2FullAccess, RDSFullAccess, and S3FullAccess roles that I will use.

I am now ready to assign on-premises groups to IAM roles. I do this by assigning the DevOps group to the EC2FullAccess, RDSFullAccess, and S3FullAccess IAM roles, and the BIMgrs group to the EC2FullAccess IAM role. Follow these steps to assign on-premises groups to IAM roles:

1. Open the Directory Service details page of your AWS Microsoft AD directory and choose the AWS Management Console link on the Apps & services tab. Choose Continue to navigate to the Add Users and Groups to Roles page.
   
2. On the Add Users and Groups to Roles page, I see the three IAM roles that I have already configured (shown in the following screenshot). If you do not have any IAM roles with a Directory Service trust policy enabled, you can create new roles or enable Directory Service for existing roles.
   
3. I will now assign the on-premises DevOps and BIMgrs groups to the EC2FullAccess role. To do so, I choose the EC2FullAccess IAM role link to navigate to the Role Detail page. Next, I choose the Add button to assign users or groups to the role, as shown in the following screenshot.
   
4. In the Add Users and Groups to Role pop-up window, I select the on-premises Active Directory forest that contains the users and groups to assign. In this example, that forest is amazondomains.com. Note: If you do not use a trust to an on-premises AD and you create users and groups in your AWS Microsoft AD directory, you can choose the default this forest to search for users in Microsoft AD.
   
5. To assign an Active Directory group, choose the Group filter above the Search for field. Type the name of the Active Directory group in the search box and choose the search button (the magnifying glass). You can see that I was able to search for the DevOps group from my on-premises Active Directory.
   
6. In this case, I added the on-premises groups, DevOps and BIMgrs, to the EC2FullAccess role. When finished, choose the Add button to assign users and groups to the IAM role. You have now successfully granted DevOps and BIMgrs on-premises AD groups full access to EC2. Users in these AD groups can now sign in to AWS Management Console using their on-premises credentials and manage EC2 instances.
   

From the Add Users and Groups to Roles page, I repeat the process to assign the remaining groups to the IAM roles. In the following screenshot, you can see that I have assigned the DevOps group to three roles and the BIMgrs group to only one role.

With my AD security groups assigned to my IAM roles, I can now add and delete on-premises users to the security groups to grant or revoke permissions to the IAM roles. Users in these security groups have access to all of their assigned roles.

7. You can optionally set the login session length for your AWS Microsoft AD directory. The default length is 1 hour, but you can increase it up to 12 hours. In my example, I set the console session time to 240 minutes (4 hours).
   

Step 4 – Connect to the AWS Management Console

I am now ready for my users to sign in to the AWS Management Console with their on-premises credentials. I emailed my users the access URL I created in Step 2: https://example-corp.awsapps.com/console. Now my users can go to the URL to sign in to the AWS Management Console.

When Mary, who is a member of DevOps group, goes to the access URL, she sees a sign-in page to connect to the AWS Management Console. In the Username box, she can enter her sign-in name in three different ways:

• Specify her on-premises NetBIOS login name (corp\mary).
• Specify her fully qualified domain name (FQDN) login name (amazondomains.com\mary).
• Use just her user name for domainless login. For more information about domainless login, see How to Easily Log On to AWS Services by Using Your On-Premises Active Directory.

Because the DevOps group is associated with three IAM roles, and because Mary is in the DevOps group, she can choose the role she wants from the list presented after she successfully logs in. The following screenshot shows this step.

If you also would like to secure the AWS Management Console with multi-factor authentication (MFA), you can add MFA to your AWS Microsoft AD configuration. To learn more about enabling MFA on Microsoft AD, see How to Enable Multi-Factor Authentication for AWS Services by Using AWS Microsoft AD and On-Premises Credentials.

Summary

AWS Microsoft AD makes it easier for you to connect to the AWS Management Console by using your on-premises credentials. It also enables you to reuse your on-premises AD security policies such as password expiration, password history, and account lockout policies while still controlling access to AWS resources.

To learn more about Directory Service, see the AWS Directory Service home page. If you have questions about this blog post, please start a new thread on the Directory Service forum.

– Vijay

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