Creating the Amazon EBS CSI driver IAM role

The Amazon EBS CSI plugin requires IAM permissions to make calls to AWS APIs on your behalf. For more information, see Set up driver permission on GitHub.

Note

Pods will have access to the permissions that are assigned to the IAM role unless you block access to IMDS. For more information, see Security best practices for Amazon EKS.

Prerequisites

• An existing cluster.

• An existing AWS Identity and Access Management (IAM) OpenID Connect (OIDC) provider for your cluster. To determine whether you already have one, or to create one, see Creating an IAM OIDC provider for your cluster.

The following procedure shows you how to create an IAM role and attach the AWS managed policy to it. You can use eksctl, the AWS Management Console, or the AWS CLI.

Note

The specific steps in this procedure are written for using the driver as an Amazon EKS add-on. Different steps are needed to use the driver as a self-managed add-on.

eksctl

To create your Amazon EBS CSI plugin IAM role with eksctl

1. Create an IAM role and attach a policy. AWS maintains an AWS managed policy or you can create your own custom policy. You can create an IAM role and attach the AWS managed policy with the following command. Replace my-cluster with the name of your cluster. The command deploys an AWS CloudFormation stack that creates an IAM role and attaches the IAM policy to it. If your cluster is in the AWS GovCloud (US-East) or AWS GovCloud (US-West) AWS Regions, then replace arn:aws: with arn:aws-us-gov:.

   eksctl create iamserviceaccount \
       --name ebs-csi-controller-sa \
       --namespace kube-system \
       --cluster my-cluster \
       --role-name AmazonEKS_EBS_CSI_DriverRole \
       --role-only \
       --attach-policy-arn arn:aws:iam::aws:policy/service-role/AmazonEBSCSIDriverPolicy \
       --approve

2. If you use a custom KMS key for encryption on your Amazon EBS volumes, customize the IAM role as needed. For example, do the following:

   1. Copy and paste the following code into a new kms-key-for-encryption-on-ebs.json file. Replace custom-key-arn with the custom KMS key ARN.

      {
        "Version": "2012-10-17",
        "Statement": [
          {
            "Effect": "Allow",
            "Action": [
              "kms:CreateGrant",
              "kms:ListGrants",
              "kms:RevokeGrant"
            ],
            "Resource": ["custom-key-arn"],
            "Condition": {
              "Bool": {
                "kms:GrantIsForAWSResource": "true"
              }
            }
          },
          {
            "Effect": "Allow",
            "Action": [
              "kms:Encrypt",
              "kms:Decrypt",
              "kms:ReEncrypt*",
              "kms:GenerateDataKey*",
              "kms:DescribeKey"
            ],
            "Resource": ["custom-key-arn"]
          }
        ]
      }

   2. Create the policy. You can change KMS_Key_For_Encryption_On_EBS_Policy to a different name. However, if you do, make sure to change it in later steps, too.

      aws iam create-policy \
        --policy-name KMS_Key_For_Encryption_On_EBS_Policy \
        --policy-document file://kms-key-for-encryption-on-ebs.json
      

   3. Attach the IAM policy to the role with the following command. Replace 111122223333 with your account ID. If your cluster is in the AWS GovCloud (US-East) or AWS GovCloud (US-West) AWS Regions, then replace arn:aws: with arn:aws-us-gov:.

      aws iam attach-role-policy \
        --policy-arn arn:aws:iam::111122223333:policy/KMS_Key_For_Encryption_On_EBS_Policy \
        --role-name AmazonEKS_EBS_CSI_DriverRole

AWS Management Console

To create your Amazon EBS CSI plugin IAM role with the AWS Management Console

1. Open the IAM console at https://console.aws.amazon.com/iam/.

2. In the left navigation pane, choose Roles.

3. On the Roles page, choose Create role.

4. On the Select trusted entity page, do the following:

   1. In the Trusted entity type section, choose Web identity.

   2. For Identity provider, choose the OpenID Connect provider URL for your cluster (as shown under Overview in Amazon EKS).

   3. For Audience, choose sts.amazonaws.com.

   4. Choose Next.

5. On the Add permissions page, do the following:

   1. In the Filter policies box, enter AmazonEBSCSIDriverPolicy.

   2. Select the check box to the left of the AmazonEBSCSIDriverPolicy returned in the search.

   3. Choose Next.

6. On the Name, review, and create page, do the following:

   1. For Role name, enter a unique name for your role, such as AmazonEKS_EBS_CSI_DriverRole.

   2. Under Add tags (Optional), add metadata to the role by attaching tags as key-value pairs. For more information about using tags in IAM, see Tagging IAM resources in the IAM User Guide.

   3. Choose Create role.

7. After the role is created, choose the role in the console to open it for editing.

8. Choose the Trust relationships tab, and then choose Edit trust policy.

9. Find the line that looks similar to the following line:

   "oidc.eks.region-code.amazonaws.com/id/EXAMPLED539D4633E53DE1B71EXAMPLE:aud": "sts.amazonaws.com"

   Add a comma to the end of the previous line, and then add the following line after the previous line. Replace region-code with the AWS Region that your cluster is in. Replace EXAMPLED539D4633E53DE1B71EXAMPLE with your cluster's OIDC provider ID.

   "oidc.eks.region-code.amazonaws.com/id/EXAMPLED539D4633E53DE1B71EXAMPLE:sub": "system:serviceaccount:kube-system:ebs-csi-controller-sa"

10. Choose Update policy to finish.

11. If you use a custom KMS key for encryption on your Amazon EBS volumes, customize the IAM role as needed. For example, do the following:

    1. In the left navigation pane, choose Policies.

    2. On the Policies page, choose Create Policy.

    3. On the Create policy page, choose the JSON tab.

    4. Copy and paste the following code into the editor, replacing custom-key-arn with the custom KMS key ARN.

       {
         "Version": "2012-10-17",
         "Statement": [
           {
             "Effect": "Allow",
             "Action": [
               "kms:CreateGrant",
               "kms:ListGrants",
               "kms:RevokeGrant"
             ],
             "Resource": ["custom-key-arn"],
             "Condition": {
               "Bool": {
                 "kms:GrantIsForAWSResource": "true"
               }
             }
           },
           {
             "Effect": "Allow",
             "Action": [
               "kms:Encrypt",
               "kms:Decrypt",
               "kms:ReEncrypt*",
               "kms:GenerateDataKey*",
               "kms:DescribeKey"
             ],
             "Resource": ["custom-key-arn"]
           }
         ]
       }

    5. Choose Next: Tags.

    6. On the Add tags (Optional) page, choose Next: Review.

    7. For Name, enter a unique name for your policy (for example, KMS_Key_For_Encryption_On_EBS_Policy).

    8. Choose Create policy.

    9. In the left navigation pane, choose Roles.

    10. Choose the AmazonEKS_EBS_CSI_DriverRole in the console to open it for editing.

    11. From the Add permissions dropdown list, choose Attach policies.

    12. In the Filter policies box, enter KMS_Key_For_Encryption_On_EBS_Policy.

    13. Select the check box to the left of the KMS_Key_For_Encryption_On_EBS_Policy that was returned in the search.

    14. Choose Attach policies.

AWS CLI

To create your Amazon EBS CSI plugin IAM role with the AWS CLI

1. View your cluster's OIDC provider URL. Replace my-cluster with your cluster name. If the output from the command is None, review the Prerequisites.

   aws eks describe-cluster --name my-cluster --query "cluster.identity.oidc.issuer" --output text
   

   An example output is as follows.

   https://oidc.eks.region-code.amazonaws.com/id/EXAMPLED539D4633E53DE1B71EXAMPLE

2. Create the IAM role, granting the AssumeRoleWithWebIdentity action.

   1. Copy the following contents to a file that's named aws-ebs-csi-driver-trust-policy.json. Replace 111122223333 with your account ID. Replace EXAMPLED539D4633E53DE1B71EXAMPLE and region-code with the values returned in the previous step. If your cluster is in the AWS GovCloud (US-East) or AWS GovCloud (US-West) AWS Regions, then replace arn:aws: with arn:aws-us-gov:.

      {
        "Version": "2012-10-17",
        "Statement": [
          {
            "Effect": "Allow",
            "Principal": {
              "Federated": "arn:aws:iam::111122223333:oidc-provider/oidc.eks.region-code.amazonaws.com/id/EXAMPLED539D4633E53DE1B71EXAMPLE"
            },
            "Action": "sts:AssumeRoleWithWebIdentity",
            "Condition": {
              "StringEquals": {
                "oidc.eks.region-code.amazonaws.com/id/EXAMPLED539D4633E53DE1B71EXAMPLE:aud": "sts.amazonaws.com",
                "oidc.eks.region-code.amazonaws.com/id/EXAMPLED539D4633E53DE1B71EXAMPLE:sub": "system:serviceaccount:kube-system:ebs-csi-controller-sa"
              }
            }
          }
        ]
      }

   2. Create the role. You can change AmazonEKS_EBS_CSI_DriverRole to a different name. If you change it, make sure to change it in later steps.

      aws iam create-role \
        --role-name AmazonEKS_EBS_CSI_DriverRole \
        --assume-role-policy-document file://"aws-ebs-csi-driver-trust-policy.json"
      

3. Attach a policy. AWS maintains an AWS managed policy or you can create your own custom policy. Attach the AWS managed policy to the role with the following command. If your cluster is in the AWS GovCloud (US-East) or AWS GovCloud (US-West) AWS Regions, then replace arn:aws: with arn:aws-us-gov:.

   aws iam attach-role-policy \
     --policy-arn arn:aws:iam::aws:policy/service-role/AmazonEBSCSIDriverPolicy \
     --role-name AmazonEKS_EBS_CSI_DriverRole
   

4. If you use a custom KMS key for encryption on your Amazon EBS volumes, customize the IAM role as needed. For example, do the following:

   1. Copy and paste the following code into a new kms-key-for-encryption-on-ebs.json file. Replace custom-key-arn with the custom KMS key ARN.

      {
        "Version": "2012-10-17",
        "Statement": [
          {
            "Effect": "Allow",
            "Action": [
              "kms:CreateGrant",
              "kms:ListGrants",
              "kms:RevokeGrant"
            ],
            "Resource": ["custom-key-arn"],
            "Condition": {
              "Bool": {
                "kms:GrantIsForAWSResource": "true"
              }
            }
          },
          {
            "Effect": "Allow",
            "Action": [
              "kms:Encrypt",
              "kms:Decrypt",
              "kms:ReEncrypt*",
              "kms:GenerateDataKey*",
              "kms:DescribeKey"
            ],
            "Resource": ["custom-key-arn"]
          }
        ]
      }

   2. Create the policy. You can change KMS_Key_For_Encryption_On_EBS_Policy to a different name. However, if you do, make sure to change it in later steps, too.

      aws iam create-policy \
        --policy-name KMS_Key_For_Encryption_On_EBS_Policy \
        --policy-document file://kms-key-for-encryption-on-ebs.json
      

   3. Attach the IAM policy to the role with the following command. Replace 111122223333 with your account ID. If your cluster is in the AWS GovCloud (US-East) or AWS GovCloud (US-West) AWS Regions, then replace arn:aws: with arn:aws-us-gov:.

      aws iam attach-role-policy \
        --policy-arn arn:aws:iam::111122223333:policy/KMS_Key_For_Encryption_On_EBS_Policy \
        --role-name AmazonEKS_EBS_CSI_DriverRole
      

Now that you have created the Amazon EBS CSI driver IAM role, you can continue to Adding the Amazon EBS CSI driver add-on. When you deploy the plugin in that procedure, it creates and is configured to use a service account that's named ebs-csi-controller-sa. The service account is bound to a Kubernetes clusterrole that's assigned the required Kubernetes permissions.