Launch an EKS Managed Node Group

This terraform module will deploy the following services:

• EKS Node Group
• Auto Scaling Group
• IAM Role
• IAM Role Policy

Usage Instructions

Example

module "eks_worker" {
  source = "github.com/terrablocks/aws-eks-managed-node-group.git"

  cluster_name = "eks-cluster"
  subnet_ids   = ["subnet-xxxx", "subnet-yyyy"]
}

Requirements

Name	Version
terraform	>= 0.13
aws	>= 3.44.0

Inputs

Name	Description	Type	Default	Required
cluster_name	Name of EKS cluster	string	n/a	yes
ng_name	Name of EKS Node Group. Default: {cluster_name}-ng	string	""	no
create_ng_role	Whether to create new IAM role for EKS nodes	bool	true	no
ng_role_arn	ARN of IAM role to associate with EKS nodes. Leave it blank to create IAM role with required permissions	string	""	no
subnet_ids	List of subnet ids to be used for launching EKS nodes	list(string)	n/a	yes
launch_template	A config block with launch template details { id = ID of the EC2 Launch Template to use. Note: Either id or name is required name = Name of the EC2 Launch Template to use. Note: Either id or name is required version = EC2 Launch Template version to use for launching instances }	map(any)	{}	no
desired_size	Initial number of nodes to launch	number	2	no
max_size	Maximum number of nodes	number	4	no
min_size	Minimum number of nodes to maintain at any given point of time	number	2	no
capacity_type	Type of purchase option to be used for EKS node. Possible Values: ON_DEMAND or SPOT	string	"ON_DEMAND"	no
instance_type	Type of instance to be used for EKS nodes	string	"t3.medium"	no
disk_size	Size of each EBS volume attached to EKS node	number	20	no
labels	Key Value pair of Kubernetes labels to apply on nodes	map(string)	{}	no
ami_type	Type of AMI to be used for EKS node. Supported values: AL2_x86_64, AL2_ARM_64, AL2_x86_64_GPU(AMI with GPU support)	string	"AL2_x86_64"	no
remote_access	A config block with EC2 remote access details { ssh_key_name = Name of SSH key pair to associate to instances launched via node group sg_ids = Security group ids to attach to instances launched via node group }	map(any)	{}	no
taints	List of taint block to associate with node group. Maximum of 50 taints per node group are supported { key = Key of taint value = (Optional) Value of taint effect = Effect of taint. Possible values: NO_SCHEDULE, NO_EXECUTE or PREFER_NO_SCHEDULE }	list(any)	[]	no
tags	Key Value pair to associate with node group	map(string)	{}	no

Outputs

Name	Description
arn	ARN of EKS node group created
id	EKS Cluster name and EKS Node Group name separated by a colon
name	Name of the managed node group associated with the EKS cluster
cluster_name	Name of the EKS cluster attached to the node group
role_arn	ARN of the IAM role associated with EKS node group
role_name	Name of the IAM role associated with EKS node group
status	Status of the EKS node group

Cluster Autoscaler Setup (Source: AWS)

To enable Cluster Autoscaler execute the following steps:

Deploy Cluster Autoscaler:

kubectl apply -f https://raw.githubusercontent.com/kubernetes/autoscaler/master/cluster-autoscaler/cloudprovider/aws/examples/cluster-autoscaler-autodiscover.yaml

Add annotation to cluster-autoscaler deployment:

kubectl -n kube-system annotate deployment.apps/cluster-autoscaler cluster-autoscaler.kubernetes.io/safe-to-evict="false"

Edit custer-autoscaler deployment and do the required changes:

kubectl -n kube-system edit deployment.apps/cluster-autoscaler

Replace <YOUR CLUSTER NAME> with your cluster's name, and add the following options:

• --balance-similar-node-groups
• --skip-nodes-with-system-pods=false

Example:

spec:
  containers:
  - command:
  - ./cluster-autoscaler
  - --v=4
  - --stderrthreshold=info
  - --cloud-provider=aws
  - --skip-nodes-with-local-storage=false
  - --expander=least-waste
  - --node-group-auto-discovery=asg:tag=k8s.io/cluster-autoscaler/enabled,k8s.io/cluster-autoscaler/<YOUR CLUSTER NAME>
  - --balance-similar-node-groups
  - --skip-nodes-with-system-pods=false

Set image for cluster-autoscaler deployment:

• Visit Cluster Autoscaler releases to get the latest semantic version number for your kubernetes version. Eg: If your k8s version is 1.16, look for the latest release of cluster-autoscaler beginning with your k8s version and note down the semantic version (1.16.x)
• You can replace us with asia or eu as per proximity

kubectl -n kube-system set image deployment.apps/cluster-autoscaler cluster-autoscaler=us.gcr.io/k8s-artifacts-prod/autoscaling/cluster-autoscaler:v1.16.x

Verify Cluster Autoscaler deployment by checking logs:

kubectl -n kube-system logs -f deployment.apps/cluster-autoscaler