terraform-aws-eks-node-group

A Terraform module to create an EKS node group that uses an autoscaling group.

IMPORTANT

This module allows the use of instance attributes and mixed instance policies with Spot for EKS nodes.
However, currently this requires a separate launch template and the use of aws_autoscaling_group rather than a eks_node_group resource.
Watch aws/containers-roadmap#1297 and update this module accordingly.

Requirements

VPC
EKS Cluster
Security Groups (for incoming traffic, etc)

Example

module "eks_node_group" {
  source                = "../../"
  
  # Use a custom asg and launch template to use mixed instances policy
  # and/or instance attributes
  go_turbo              = true

  instance_requirements = {
    memory_gib_per_vcpu = {
      min = 2
      max = 4
    }

    memory_mib = {
      min = 2048
      max = 32768
    }

    network_interface_count = {
      min = 1
      max = 16
    }

    vcpu_count = {
      min = 2
      max = 4
    }
  }

  network_interfaces = [
    {
      delete_on_termination   = true
      description             = "eth0"
      device_index            = 0
    },
    {
      delete_on_termination   = true
      description             = "eth1"
      device_index            = 1
    }
  ]
  
  mixed_instances_policy = {
    instances_distribution = {
      on_demand_base_capacity                   = 0
      on_demand_percentage_above_base_capacity  = 10
      spot_allocation_strategy                  = "capacity-optimized"
      spot_instance_pools                       = 0
    }
  }

  use_mixed_instances_policy  = true
  capacity_rebalance          = true
  vpc_zone_identifier         = module.vpc.private_subnets
  vpc_id                      = module.vpc.vpc_id
  allowed_security_groups     = [module.eks_sg.security_group_id]
  min_size                    = 1
  max_size                    = 2
  cluster_name                = local.cluster_name
  kubernetes_version          = "1.23"
  eks_cluster_endpoint        = aws_eks_cluster.example.endpoint
  eks_cluster_auth_token      = data.aws_eks_cluster_auth.example.token
  eks_cluster_ca_certificate  = base64decode(aws_eks_cluster.example.certificate_authority[0].data)
}

Inputs

We are using the terraform-aws-autoscaling module for the node group ASG where mixed instance policies are required. For a list of Inputs go to https://github.com/terraform-aws-modules/terraform-aws-autoscaling#inputs.

Module-specific inputs are:

go_turbo
cluster_name
eks_cluster_endpoint
eks_cluster_auth_token
eks_cluster_ca_certificate
allowed_security_groups
kubernetes_versions
wait_for_cluster_cmd
wait_for_cluster_interpreter
subnet_ids: For use with eks_node_group. Identifiers of EC2 Subnets to associate with the EKS Node Group. These subnets must have the following resource tag: kubernetes.io/cluster/CLUSTER_NAME (where CLUSTER_NAME is replaced with the name of the EKS Cluster).

Outputs

We are using the terraform-aws-autoscaling module for the node group ASG where mixed instance policies are required. For a list of Outputs go to https://github.com/terraform-aws-modules/terraform-aws-autoscaling#outputs.

Module-specific outputs are: