Adding EKS clusters

GitLab supports adding new and existing EKS clusters.

EKS requirements

Before creating your first cluster on Amazon EKS with GitLab’s integration, make sure the following requirements are met:

Additional requirements for self-managed instances

If you are using a self-managed GitLab instance, GitLab must first be configured with a set of Amazon credentials. These credentials will be used to assume an Amazon IAM role provided by the user creating the cluster. Create an IAM user and ensure it has permissions to assume the role(s) that your users will use to create EKS clusters.

For example, the following policy document allows assuming a role whose name starts with gitlab-eks- in account 123456789012:

{
  "Version": "2012-10-17",
  "Statement": {
    "Effect": "Allow",
    "Action": "sts:AssumeRole",
    "Resource": "arn:aws:iam::123456789012:role/gitlab-eks-*"
  }
}

Generate an access key for the IAM user, and configure GitLab with the credentials:

  1. Navigate to Admin Area > Settings > General and expand the Amazon EKS section.
  2. Check Enable Amazon EKS integration.
  3. Enter the account ID and access key credentials into the respective Account ID, Access key ID and Secret access key fields.
  4. Click Save changes.

New EKS cluster

Introduced in GitLab 12.5.

To create and add a new Kubernetes cluster to your project, group, or instance:

  1. Navigate to your:
    • Project’s Operations > Kubernetes page, for a project-level cluster.
    • Group’s Kubernetes page, for a group-level cluster.
    • Admin Area > Kubernetes, for an instance-level cluster.
  2. Click Add Kubernetes cluster.
  3. Under the Create new cluster tab, click Amazon EKS. You will be provided with an Account ID and External ID needed for later steps.
  4. In the IAM Management Console, create an IAM policy:
    1. From the left panel, select Policies.
    2. Click Create Policy, which opens a new window.
    3. Select the JSON tab, and paste the following snippet in place of the existing content. These permissions give GitLab the ability to create resources, but not delete them:

      {
          "Version": "2012-10-17",
          "Statement": [
              {
                  "Effect": "Allow",
                  "Action": [
                      "autoscaling:CreateAutoScalingGroup",
                      "autoscaling:DescribeAutoScalingGroups",
                      "autoscaling:DescribeScalingActivities",
                      "autoscaling:UpdateAutoScalingGroup",
                      "autoscaling:CreateLaunchConfiguration",
                      "autoscaling:DescribeLaunchConfigurations",
                      "cloudformation:CreateStack",
                      "cloudformation:DescribeStacks",
                      "ec2:AuthorizeSecurityGroupEgress",
                      "ec2:AuthorizeSecurityGroupIngress",
                      "ec2:RevokeSecurityGroupEgress",
                      "ec2:RevokeSecurityGroupIngress",
                      "ec2:CreateSecurityGroup",
                      "ec2:createTags",
                      "ec2:DescribeImages",
                      "ec2:DescribeKeyPairs",
                      "ec2:DescribeRegions",
                      "ec2:DescribeSecurityGroups",
                      "ec2:DescribeSubnets",
                      "ec2:DescribeVpcs",
                      "eks:CreateCluster",
                      "eks:DescribeCluster",
                      "iam:AddRoleToInstanceProfile",
                      "iam:AttachRolePolicy",
                      "iam:CreateRole",
                      "iam:CreateInstanceProfile",
                      "iam:CreateServiceLinkedRole",
                      "iam:GetRole",
                      "iam:ListRoles",
                      "iam:PassRole",
                      "ssm:GetParameters"
                  ],
                  "Resource": "*"
              }
          ]
      }
      

      If an error is encountered during the creation process, changes will not be rolled back and you must remove resources manually. You can do this by deleting the relevant CloudFormation stack

    4. Click Review policy.
    5. Enter a suitable name for this policy, and click Create Policy. You can now close this window.
  5. In the IAM Management Console, create an EKS management IAM role. To do so, follow the Amazon EKS cluster IAM role instructions to create a IAM role suitable for managing the AWS EKS cluster’s resources on your behalf. In addition to the policies that guide suggests, you must also include the AmazonEKSClusterPolicy policy for this role in order for GitLab to manage the EKS cluster correctly.
  6. In the IAM Management Console, create an IAM role:
    1. From the left panel, select Roles.
    2. Click Create role.
    3. Under Select type of trusted entity, select Another AWS account.
    4. Enter the Account ID from GitLab into the Account ID field.
    5. Check Require external ID.
    6. Enter the External ID from GitLab into the External ID field.
    7. Click Next: Permissions, and select the policy you just created.
    8. Click Next: Tags, and optionally enter any tags you wish to associate with this role.
    9. Click Next: Review.
    10. Enter a role name and optional description into the fields provided.
    11. Click Create role, the new role name will appear at the top. Click on its name and copy the Role ARN from the newly created role.
  7. In GitLab, enter the copied role ARN into the Role ARN field.
  8. In the Cluster Region field, enter the region you plan to use for your new cluster. GitLab will authenticate you have access to this region when authenticating your role.
  9. Click Authenticate with AWS.
  10. Choose your cluster’s settings:
    • Kubernetes cluster name - The name you wish to give the cluster.
    • Environment scope - The associated environment to this cluster.
    • Kubernetes version - The Kubernetes version to use.
    • Service role - Select the EKS IAM role you created earlier to allow Amazon EKS and the Kubernetes control plane to manage AWS resources on your behalf.

      Note: This IAM role is not the IAM role you created in the previous step. It should be the one you created much earlier by following the Amazon EKS cluster IAM role guide.
    • Key pair name - Select the key pair that you can use to connect to your worker nodes if required.
    • VPC - Select a VPC to use for your EKS Cluster resources.
    • Subnets - Choose the subnets in your VPC where your worker nodes will run. You must select at least two.
    • Security group - Choose the security group to apply to the EKS-managed Elastic Network Interfaces that are created in your worker node subnets.
    • Instance type - The instance type of your worker nodes.
    • Node count - The number of worker nodes.
    • GitLab-managed cluster - Leave this checked if you want GitLab to manage namespaces and service accounts for this cluster. See the Managed clusters section for more information.
  11. Finally, click the Create Kubernetes cluster button.

After about 10 minutes, your cluster will be ready to go. You can now proceed to install some pre-defined applications.

Note: You will need to add your AWS external ID to the IAM Role in the AWS CLI to manage your cluster using kubectl.

Troubleshooting creating a new cluster

The following errors are commonly encountered when creating a new cluster.

Error: Request failed with status code 422

When submitting the initial authentication form, GitLab returns a status code 422 error when it can’t determine the role or region you’ve provided. Make sure you’ve correctly configured your role with the Account ID and External ID provided by GitLab. In GitLab, make sure to enter the correct Role ARN. Make sure you also have access to the chosen region.

Could not load Security Groups for this VPC

When populating options in the configuration form, GitLab returns this error because GitLab has successfully assumed your provided role, but the role has insufficient permissions to retrieve the resources needed for the form. Make sure you’ve assigned the role the correct permissions.

ROLLBACK_FAILED during cluster creation

The creation process halted because GitLab encountered an error when creating one or more resources. You can inspect the associated CloudFormation stack to find the specific resources that failed to create.

If the Cluster resource failed with the error The provided role doesn't have the Amazon EKS Managed Policies associated with it., the role specified in Role name is not configured correctly.

Note: This role should be the role you created by following the EKS cluster IAM role guide. In addition to the policies that guide suggests, you must also include the AmazonEKSClusterPolicy policy for this role in order for GitLab to manage the EKS cluster correctly.

Existing EKS cluster

For information on adding an existing EKS cluster, see Existing Kubernetes cluster.

Create a default Storage Class

Amazon EKS doesn’t have a default Storage Class out of the box, which means requests for persistent volumes will not be automatically fulfilled. As part of Auto DevOps, the deployed PostgreSQL instance requests persistent storage, and without a default storage class it will fail to start.

If a default Storage Class doesn’t already exist and is desired, follow Amazon’s guide on storage classes to create one.

Alternatively, disable PostgreSQL by setting the project variable POSTGRES_ENABLED to false.

Deploy the app to EKS

With RBAC disabled and services deployed, Auto DevOps can now be leveraged to build, test, and deploy the app.

Enable Auto DevOps if not already enabled. If a wildcard DNS entry was created resolving to the Load Balancer, enter it in the domain field under the Auto DevOps settings. Otherwise, the deployed app will not be externally available outside of the cluster.

Deploy Pipeline

A new pipeline will automatically be created, which will begin to build, test, and deploy the app.

After the pipeline has finished, your app will be running in EKS and available to users. Click on CI/CD > Environments.

Deployed Environment

You will see a list of the environments and their deploy status, as well as options to browse to the app, view monitoring metrics, and even access a shell on the running pod.