Examples

---

Merging multiple configuration objects

When using the IMDS configuration source (--config-source=imds://user-data), nodeadm will merge any configuration objects it discovers before configuring your node.

With the following user data:

MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="BOUNDARY"

--BOUNDARY
Content-Type: application/node.eks.aws

---
apiVersion: node.eks.aws/v1alpha1
kind: NodeConfig
spec:
  cluster:
    name: my-cluster
    apiServerEndpoint: https://example.com
    certificateAuthority: Y2VydGlmaWNhdGVBdXRob3JpdHk=
    cidr: 10.100.0.0/16

--BOUNDARY--
Content-Type: application/node.eks.aws

---
apiVersion: node.eks.aws/v1alpha1
kind: NodeConfig
spec:
  kubelet:
    config:
      shutdownGracePeriod: 30s
      featureGates:
        DisableKubeletCloudCredentialProviders: true

--BOUNDARY--

The configuration nodeadm will use is:

---
apiVersion: node.eks.aws/v1alpha1
kind: NodeConfig
spec:
  cluster:
    name: my-cluster
    apiServerEndpoint: https://example.com
    certificateAuthority: Y2VydGlmaWNhdGVBdXRob3JpdHk=
    cidr: 10.100.0.0/16
  kubelet:
    config:
      shutdownGracePeriod: 30s
      featureGates:
        DisableKubeletCloudCredentialProviders: true

The configuration objects will be merged in the order they appear in the MIME multi-part document, meaning the value in the lattermost configuration object will take precedence.

---

Using instance ID as node name (experimental)

When the InstanceIdNodeName feature gate is enabled, nodeadm will use the EC2 instance's ID (e.g. i-abcdefg1234) as the name of the Node object created by kubelet, instead of the EC2 instance's private DNS Name (e.g. ip-192-168-1-1.ec2.internal). There are several benefits of doing this: 1. Your Node names are more meaningful in, for example, the output of kubectl get nodes. 2. The Node name, which is in the critical path of kubelet authentication, is non-volatile. While the private DNS name of an instance may change, its ID cannot. 3. The ec2:DescribeInstances permission can be removed from your node role's IAM policy; this is no longer necessary.

To enable this feature, you will need to:

1. Create a new worker node IAM role
   • ⚠️ Note: you should create a new role when migrating an existing cluster to avoid authentication failures on existing nodes.
2. Update the aws-auth ConfigMap with above created role. For example:

- groups:
  - system:bootstrappers
  - system:nodes
  rolearn: $ROLE_CREATED_ABOVE
  username: system:node:{{SessionName}}

1. Enable the feature gate in your user data:

---
apiVersion: node.eks.aws/v1alpha1
kind: NodeConfig
spec:
  featureGates:
    InstanceIdNodeName: true

---

Configuring containerd

Additional containerd configuration can be supplied in your NodeConfig. The values in your inline TOML document will overwrite any default value set by nodeadm.

The following configuration object:

---
apiVersion: node.eks.aws/v1alpha1
kind: NodeConfig
spec:
  cluster: ...
  containerd:
    config: |
      [plugins."io.containerd.grpc.v1.cri".containerd]
      discard_unpacked_layers = false

Can be used to disable deletion of unpacked image layers in the containerd content store.

---

Modifying container RLIMITs

If your workload requires different RLIMITs than the defaults, you can use the baseRuntimeSpec option of containerd to override them:

---
apiVersion: node.eks.aws/v1alpha1
kind: NodeConfig
spec:
  cluster: ...
  containerd:
    baseRuntimeSpec:
      process:
        rlimits:
          - type: RLIMIT_NOFILE
            soft: 1024
            hard: 1024