Chapter 4. AWS Load Balancer Operator

Procedure

1. Download the CredentialsRequest custom resource (CR) and store it in a directory by running the following command:

   $ curl --create-dirs -o <credentials_requests_dir>/operator.yaml https://raw.githubusercontent.com/openshift/aws-load-balancer-operator/main/hack/operator-credentials-request.yaml

2. Use the ccoctl utility to create an AWS IAM role by running the following command:

   $ ccoctl aws create-iam-roles \
       --name <name> \
       --region=<aws_region> \
       --credentials-requests-dir=<credentials_requests_dir> \
       --identity-provider-arn <oidc_arn>

   Example output

   2023/09/12 11:38:57 Role arn:aws:iam::777777777777:role/<name>-aws-load-balancer-operator-aws-load-balancer-operator created 1
   2023/09/12 11:38:57 Saved credentials configuration to: /home/user/<credentials_requests_dir>/manifests/aws-load-balancer-operator-aws-load-balancer-operator-credentials.yaml
   2023/09/12 11:38:58 Updated Role policy for Role <name>-aws-load-balancer-operator-aws-load-balancer-operator created

   1

   Note the Amazon Resource Name (ARN) of an AWS IAM role that was created for the AWS Load Balancer Operator, such as arn:aws:iam::777777777777:role/<name>-aws-load-balancer-operator-aws-load-balancer-operator.

   Note

   The length of an AWS IAM role name must be less than or equal to 12 characters.

Procedure

1. Download the CredentialsRequest custom resource (CR) and store it in a directory by running the following command:

   $ curl --create-dirs -o <credentials_requests_dir>/controller.yaml https://raw.githubusercontent.com/openshift/aws-load-balancer-operator/main/hack/controller/controller-credentials-request.yaml

2. Use the ccoctl utility to create an AWS IAM role by running the following command:

   $ ccoctl aws create-iam-roles \
       --name <name> \
       --region=<aws_region> \
       --credentials-requests-dir=<credentials_requests_dir> \
       --identity-provider-arn <oidc_arn>

   Example output

   2023/09/12 11:38:57 Role arn:aws:iam::777777777777:role/<name>-aws-load-balancer-operator-aws-load-balancer-controller created 1
   2023/09/12 11:38:57 Saved credentials configuration to: /home/user/<credentials_requests_dir>/manifests/aws-load-balancer-operator-aws-load-balancer-controller-credentials.yaml
   2023/09/12 11:38:58 Updated Role policy for Role <name>-aws-load-balancer-operator-aws-load-balancer-controller created

   1

   Note the Amazon Resource Name (ARN) of an AWS IAM role that was created for the AWS Load Balancer Controller, such as arn:aws:iam::777777777777:role/<name>-aws-load-balancer-operator-aws-load-balancer-controller.

   Note

   The length of an AWS IAM role name must be less than or equal to 12 characters.

Procedure

1. Identify the cluster infrastructure ID and the cluster OpenID Connect (OIDC) DNS by running the following commands:

   1. Identify the ROSA cluster ID:

      $ rosa describe cluster --cluster=<cluster_name> | grep -i 'Infra ID'

      or

      $ oc get infrastructure cluster -o json | jq -r '.status.infrastructureName'

   2. Identify the ROSA cluster OIDC DNS by using the following rosa CLI command:

      $ rosa describe cluster --cluster=<cluster_name> | grep -i OIDC 1

      1

      An OIDC DNS example is oidc.op1.openshiftapps.com/28q7fsn54m2jjts3kd556aij4mu9omah.

      or

      $ oc get authentication.config cluster -o=jsonpath="{.spec.serviceAccountIssuer}"

   3. Locate the OIDC Amazon Resource Name (ARN) information on the AWS Web Console by navigating to IAM Access management Identity providers. An OIDC ARN example is arn:aws:iam::777777777777:oidc-provider/<oidc_dns_url>.
   4. Save the output from the commands. You will use this information in future steps within this procedure.

2. Create the AWS IAM policy required for the AWS Load Balancer Operator by using the AWS CLI.

   1. Log in to the ROSA cluster as a user with the dedicated-admin role and create a new project using the following command:

      $ oc new-project aws-load-balancer-operator

   2. Assign the following trust policy to the newly-created AWS IAM role:

      $ IDP='{Cluster_OIDC_Endpoint}'

      $ IDP_ARN="arn:aws:iam::{AWS_AccountNo}:oidc-provider/${IDP}" 1

      1

      Replace {AWS_AccountNo} with your AWS account number and {Cluster_OIDC_Endpoint} with the OIDC DNS identified earlier in this procedure.

   3. Verify that the trsut policy was assigned to the AWS IAM role.

      Example output

      $ cat EOF albo-operator-trusted-policy.json
      {
          "Version": "2012-10-17",
          "Statement": [
              {
                  "Effect": "Allow",
                  "Principal": {
                      "Federated": "${IDP_ARN}"
                  },
                  "Action": "sts:AssumeRoleWithWebIdentity",
                  "Condition": {
                      "StringEquals": {
                          "${IDP}:sub": "system:serviceaccount:aws-load-balancer-operator:aws-load-balancer-operator-controller-manager"
                      }
                  }
              }
          ]
      }
      EOF

      Important

      Do not include the https portion of the OIDC DNS URL when replacing {Cluster_OIDC_Endpoint} with the OIDC DNS you identified earlier. Only the alphanumeric information that follows the / within the URL is needed.

   4. Create and verify the role by using the generated trust policy:

      $ aws iam create-role --role-name albo-operator --assume-role-policy-document file://albo-operator-trusted-policy.json

      $ OPERATOR_ROLE_ARN=$(aws iam get-role --role-name albo-operator --output json | jq -r '.Role.Arn')

      $ echo $OPERATOR_ROLE_ARN

      Example output

      ROLE arn:aws:iam::<aws_account_number>:role/albo-operator	2023-08-02T12:13:22Z
      ASSUMEROLEPOLICYDOCUMENT	2012-10-17
      STATEMENT	sts:AssumeRoleWithWebIdentity	Allow
      STRINGEQUALS system:serviceaccount:aws-load-balancer-operator:aws-load-balancer-controller-manager
      PRINCIPAL arn:aws:iam:<aws_account_number>:oidc-provider/<oidc_provider_id>

      Note

      Where arn of the AWS IAM role was created for the AWS Load Balancer Operator, such as arn:aws:iam::777777777777:role/albo-operator.

   5. Attach the operator’s permission policy to the role:

      $ curl -o albo-operator-permission-policy.json https://raw.githubusercontent.com/openshift/aws-load-balancer-operator/release-1.1/hack/operator-permission-policy.json
      $ aws iam put-role-policy --role-name albo-operator --policy-name perms-policy-albo-operator --policy-document file://albo-operator-permission-policy.json

3. Create the AWS IAM policy required for the AWS Load Balancer Controller by using the AWS CLI:

   1. Generate a trust policy file for your identity provider. The following example uses OpenID Connect:

      $ IDP='{Cluster_OIDC_Endpoint}'
      $ IDP_ARN="arn:aws:iam::{AWS_AccountNo}:oidc-provider/${IDP}"
      $ cat <EOF> albo-controller-trusted-policy.json
      {
          "Version": "2012-10-17",
          "Statement": [
              {
                  "Effect": "Allow",
                  "Principal": {
                      "Federated": "${IDP_ARN}"
                  },
                  "Action": "sts:AssumeRoleWithWebIdentity",
                  "Condition": {
                      "StringEquals": {
                          "${IDP}:sub": "system:serviceaccount:aws-load-balancer-operator:aws-load-balancer-controller-cluster"
                      }
                  }
              }
          ]
      }
      EOF

   2. Create and verify the role by using the generated trust policy:

      $ aws iam create-role --role-name albo-controller --assume-role-policy-document file://albo-controller-trusted-policy.json
      $ CONTROLLER_ROLE_ARN=$(aws iam get-role --role-name albo-controller --output json | jq -r '.Role.Arn')
      $ echo $CONTROLLER_ROLE_ARN

      Example output

      ROLE	arn:aws:iam::<aws_account_number>:role/albo-controller	2023-08-02T12:13:22Z
      ASSUMEROLEPOLICYDOCUMENT	2012-10-17
      STATEMENT	    sts:AssumeRoleWithWebIdentity	Allow
      STRINGEQUALS	system:serviceaccount:aws-load-balancer-operator:aws-load-balancer-controller-cluster
      PRINCIPAL	    arn:aws:iam:<aws_account_number>:oidc-provider/<oidc_provider_id>

      Note

      Where arn of the AWS IAM role that was created for the AWS Load Balancer Controller, such as arn:aws:iam::777777777777:role/albo-controller.

   3. Attach the controller’s permission policy to the role:

      $ curl -o albo-controller-permission-policy.json https://raw.githubusercontent.com/kubernetes-sigs/aws-load-balancer-controller/v2.4.7/docs/install/iam_policy.json
      $ aws iam put-role-policy --role-name albo-controller --policy-name perms-policy-albo-controller --policy-document file://albo-controller-permission-policy.json

4. For a ROSA with HCP cluster, add the tags necessary for subnet discovery:

   1. Add the following {Key: Value} tag to the VPC hosting the ROSA cluster and to all its subnets. Replace {Cluster Infra ID} with the Infra ID specified previously:

      kubernetes.io/cluster/${Cluster Infra ID}:owned

   2. Add the following ELBv2 {Key: Value} tags to the private subnets and, optionally, to the public subnets:

      • Private subnets: kubernetes.io/role/internal-elb:1

      • Public subnets: kubernetes.io/role/elb:1

        Note

        Internet-facing and internal load balancers will be created within the AWS Availability Zone to which these subnets belong.

        Important

        ELBv2 resources (such as ALBs and NLBs) created by AWS Load Balancer Operator do not inherit custom tags set for ROSA clusters. You must set tags separately for these resources.

5. Create the AWS Load Balancer Operator by completing the following steps:

   1. Create an OperatorGroup object by running the following command:

      $ cat EOF | oc apply -f -
      apiVersion: operators.coreos.com/v1
      kind: OperatorGroup
      metadata:
        name: aws-load-balancer-operator
        namespace: aws-load-balancer-operator
      spec:
        targetNamespaces: []
      EOF

   2. Create a Subscription object by running the following command:

      $ cat EOF | oc apply -f -
      apiVersion: operators.coreos.com/v1alpha1
      kind: Subscription
      metadata:
        name: aws-load-balancer-operator
        namespace: aws-load-balancer-operator
      spec:
        channel: stable-v1
        name: aws-load-balancer-operator
        source: redhat-operators
        sourceNamespace: openshift-marketplace
        config:
          env:
          - name: ROLEARN
            value: "<operator_role_arn>" 1
      EOF

      1

      Specifies the ARN role for the AWS Load Balancer Operator. The CredentialsRequest object uses this ARN role to provision the AWS credentials. An example of <operator_role_arn> is arn:aws:iam::<aws_account_number>:role/albo-operator.

6. Create the AWS Load Balancer Controller:

   apiVersion: networking.olm.openshift.io/v1
   kind: AWSLoadBalancerController
   metadata:
     name: cluster
   spec:
     subnetTagging: Manual
     credentialsRequestConfig:
       stsIAMRoleARN: <controller_role_arn>

   Important

   Because AWS Load Balancer Controllers do not support creating AWS Load Balancers (ALBs) associated with both AWS Availability Zones and AWS Local Zones, ROSA clusters can have ALBs associated exclusively with either AWS Local Zones or AWS Availability Zones but not both simultaneously.

Verification

1. Confirm a successful installation by running the following commands:

   1. Gather information about pods within the project:

      $ oc get pods -n aws-load-balancer-operator

   2. View the logs within the project:

      $ oc logs -n aws-load-balancer-operator deployment/aws-load-balancer-operator-controller-manager -c manager

Procedure

1. Clean up the sample application by deleting the Load Balancers created and managed by the ALBO. For more information about deleting Load Balancers, see Delete an Application Load Balancer.
2. Clean up the AWS VPC tags by removing the VPC tags that were added to the subnets for discovering subnets and for creating Application Load Balancers (ALBs). For more information, see Tag basics.
3. Clean up AWS Load Balancer Operator components by deleting both the AWS Load Balancer Operator and the Application Load Balancer Controller. For more information, see Deleting Operators from a cluster.