Custom AMI support

Setting the node AMI ID

The --node-ami flag enables a number of advanced use cases such as using a custom AMI or querying AWS in realtime to determine which AMI to use. The flag can be used for both non-GPU and GPU images.

The flag can take the AMI image id for an image to explicitly use. It also can take the following 'special' keywords:

Keyword	Description
auto	Indicates that the AMI to use for the nodes should be found by querying AWS EC2. This relates to the auto resolver.
auto-ssm	Indicates that the AMI to use for the nodes should be found by querying AWS SSM Parameter Store.

Note

When setting --node-ami to an ID string, eksctl will assume that a custom AMI has been requested. For AmazonLinux2 and Ubuntu nodes, both EKS managed and self-managed, this will mean that overrideBootstrapCommand is required. For AmazonLinux2023, since it stops using the /etc/eks/bootstrap.sh script for node bootstrapping, in favour of a nodeadm initialization process (for more information, please refer to node bootstrapping docs), overrideBootstrapCommand is not supported.

CLI flag examples:

eksctl create cluster --node-ami=auto

# with a custom ami id
eksctl create cluster --node-ami=ami-custom1234

Config file example:

nodeGroups:
  - name: ng1
    instanceType: p2.xlarge
    amiFamily: AmazonLinux2
    ami: auto
  - name: ng2
    instanceType: m5.large
    amiFamily: AmazonLinux2
    ami: ami-custom1234
managedNodeGroups:
  - name: m-ng-2
    amiFamily: AmazonLinux2
    ami: ami-custom1234
    instanceType: m5.large
    overrideBootstrapCommand: |
      #!/bin/bash
      /etc/eks/bootstrap.sh <cluster-name>

The --node-ami flag can also be used with eksctl create nodegroup.

Setting the node AMI Family

The --node-ami-family can take following keywords:

Keyword	Description
AmazonLinux2	Indicates that the EKS AMI image based on Amazon Linux 2 should be used (default).
AmazonLinux2023	Indicates that the EKS AMI image based on Amazon Linux 2023 should be used.
Ubuntu2004	Indicates that the EKS AMI image based on Ubuntu 20.04 LTS (Focal) should be used (supported for EKS ⇐ 1.29).
UbuntuPro2004	Indicates that the EKS AMI image based on Ubuntu Pro 20.04 LTS (Focal) should be used (available for EKS >= 1.27, ⇐ 1.29).
Ubuntu2204	Indicates that the EKS AMI image based on Ubuntu 22.04 LTS (Jammy) should be used (available for EKS >= 1.29).
UbuntuPro2204	Indicates that the EKS AMI image based on Ubuntu Pro 22.04 LTS (Jammy) should be used (available for EKS >= 1.29).
Ubuntu2404	Indicates that the EKS AMI image based on Ubuntu 24.04 LTS (Noble) should be used (available for EKS >= 1.31).
UbuntuPro2404	Indicates that the EKS AMI image based on Ubuntu Pro 24.04 LTS (Noble) should be used (available for EKS >= 1.31).
Bottlerocket	Indicates that the EKS AMI image based on Bottlerocket should be used.
WindowsServer2019FullContainer	Indicates that the EKS AMI image based on Windows Server 2019 Full Container should be used.
WindowsServer2019CoreContainer	Indicates that the EKS AMI image based on Windows Server 2019 Core Container should be used.
WindowsServer2022FullContainer	Indicates that the EKS AMI image based on Windows Server 2022 Full Container should be used.
WindowsServer2022CoreContainer	Indicates that the EKS AMI image based on Windows Server 2022 Core Container should be used.

CLI flag example:

eksctl create cluster --node-ami-family=AmazonLinux2

Config file example:

nodeGroups:
  - name: ng1
    instanceType: m5.large
    amiFamily: AmazonLinux2
managedNodeGroups:
  - name: m-ng-2
    instanceType: m5.large
    amiFamily: Ubuntu2204

The --node-ami-family flag can also be used with eksctl create nodegroup. eksctl requires AMI Family to be explicitly set via config file or via --node-ami-family CLI flag, whenever working with a custom AMI.

Note

At the moment, EKS managed nodegroups only support the following AMI Families when working with custom AMIs: AmazonLinux2023, AmazonLinux2, Ubuntu1804, Ubuntu2004 and Ubuntu2204

Windows custom AMI support

Only self-managed Windows nodegroups can specify a custom AMI. amiFamily should be set to a valid Windows AMI family.

The following PowerShell variables will be available to the bootstrap script:

$EKSBootstrapScriptFile
$EKSClusterName
$APIServerEndpoint
$Base64ClusterCA
$ServiceCIDR
$KubeletExtraArgs
$KubeletExtraArgsMap: A hashtable containing arguments for the kubelet, e.g., @{ 'node-labels' = ''; 'register-with-taints' = ''; 'max-pods' = '10'}
$DNSClusterIP
$ContainerRuntime

Config file example:

nodeGroups:
  - name: custom-windows
    amiFamily: WindowsServer2022FullContainer
    ami: ami-01579b74557facaf7
    overrideBootstrapCommand: |
      & $EKSBootstrapScriptFile -EKSClusterName "$EKSClusterName" -APIServerEndpoint "$APIServerEndpoint" -Base64ClusterCA "$Base64ClusterCA" -ContainerRuntime "containerd" -KubeletExtraArgs "$KubeletExtraArgs" 3>&1 4>&1 5>&1 6>&1

Bottlerocket custom AMI support

For Bottlerocket nodes, the overrideBootstrapCommand is not supported. Instead, to designate their own bootstrap container, one should use the bottlerocket field as part of the configuration file. E.g.

  nodeGroups:
  - name: bottlerocket-ng
    ami: ami-custom1234
    amiFamily: Bottlerocket
    bottlerocket:
      enableAdminContainer: true
      settings:
        bootstrap-containers:
          bootstrap:
            source: <MY-CONTAINER-URI>