When creating EKS cluster I attached a role to EKS which was required. The role I created using official documentation. To that role only AmazonEKSClusterPolicy policy is attached through which I guess creating EC2 Auto Scaling Group(action: CreateAutoScalingGroup) is not allowed, but still EKS is able to create EC2 Auto Scaling Group when I create Node Group.
Question: So how EKS is able to create an EC2 Auto Scaling Group if the role doesn't allow it?
JSON settings of AmazonEKSClusterPolicy policy:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"autoscaling:DescribeAutoScalingGroups",
"autoscaling:UpdateAutoScalingGroup",
"ec2:AttachVolume",
"ec2:AuthorizeSecurityGroupIngress",
"ec2:CreateRoute",
"ec2:CreateSecurityGroup",
"ec2:CreateTags",
"ec2:CreateVolume",
"ec2:DeleteRoute",
"ec2:DeleteSecurityGroup",
"ec2:DeleteVolume",
"ec2:DescribeInstances",
"ec2:DescribeRouteTables",
"ec2:DescribeSecurityGroups",
"ec2:DescribeSubnets",
"ec2:DescribeVolumes",
"ec2:DescribeVolumesModifications",
"ec2:DescribeVpcs",
"ec2:DescribeDhcpOptions",
"ec2:DescribeNetworkInterfaces",
"ec2:DetachVolume",
"ec2:ModifyInstanceAttribute",
"ec2:ModifyVolume",
"ec2:RevokeSecurityGroupIngress",
"ec2:DescribeAccountAttributes",
"ec2:DescribeAddresses",
"ec2:DescribeInternetGateways",
"elasticloadbalancing:AddTags",
"elasticloadbalancing:ApplySecurityGroupsToLoadBalancer",
"elasticloadbalancing:AttachLoadBalancerToSubnets",
"elasticloadbalancing:ConfigureHealthCheck",
"elasticloadbalancing:CreateListener",
"elasticloadbalancing:CreateLoadBalancer",
"elasticloadbalancing:CreateLoadBalancerListeners",
"elasticloadbalancing:CreateLoadBalancerPolicy",
"elasticloadbalancing:CreateTargetGroup",
"elasticloadbalancing:DeleteListener",
"elasticloadbalancing:DeleteLoadBalancer",
"elasticloadbalancing:DeleteLoadBalancerListeners",
"elasticloadbalancing:DeleteTargetGroup",
"elasticloadbalancing:DeregisterInstancesFromLoadBalancer",
"elasticloadbalancing:DeregisterTargets",
"elasticloadbalancing:DescribeListeners",
"elasticloadbalancing:DescribeLoadBalancerAttributes",
"elasticloadbalancing:DescribeLoadBalancerPolicies",
"elasticloadbalancing:DescribeLoadBalancers",
"elasticloadbalancing:DescribeTargetGroupAttributes",
"elasticloadbalancing:DescribeTargetGroups",
"elasticloadbalancing:DescribeTargetHealth",
"elasticloadbalancing:DetachLoadBalancerFromSubnets",
"elasticloadbalancing:ModifyListener",
"elasticloadbalancing:ModifyLoadBalancerAttributes",
"elasticloadbalancing:ModifyTargetGroup",
"elasticloadbalancing:ModifyTargetGroupAttributes",
"elasticloadbalancing:RegisterInstancesWithLoadBalancer",
"elasticloadbalancing:RegisterTargets",
"elasticloadbalancing:SetLoadBalancerPoliciesForBackendServer",
"elasticloadbalancing:SetLoadBalancerPoliciesOfListener",
"kms:DescribeKey"
],
"Resource": "*"
},
{
"Effect": "Allow",
"Action": "iam:CreateServiceLinkedRole",
"Resource": "*",
"Condition": {
"StringEquals": {
"iam:AWSServiceName": "elasticloadbalancing.amazonaws.com"
}
}
}
]
}