How can I automate the configuration of HTTP proxy for Amazon EKS containerd nodes?

Short description

For managed node groups that you created in Amazon EKS versions 1.23 or earlier, the default container runtime is Docker. If this is your use case, then follow all steps in the resolution to specify a containerd runtime. For managed node groups that are created in Amazon EKS version 1.24 or later, the default container runtime in containerd.

To use containerd in your managed node group instead of dockerd, you must specify a containerd runtime in userdata.

After you switch your managed node group to a containerd runtime, create a custom launch template with your Amazon Machine Image (AMI) ID. Then, configure the settings for your HTTP proxy and the environment values of your cluster.

Note: For nodes with Docker runtime, see How do I automate the HTTP proxy configuration for Amazon EKS worker nodes with Docker?

Resolution

Create a custom launch template

To specify containerd as the runtime and create a custom launch template, complete the following steps:

1. Specify containerd as the runtime in your managed node group. In userdata, use the --container-runtime=containerd option for bootstrap.sh.

2. Create a custom launch template with the AMI ID. If you don't do this, then the managed nodes group automatically merges userdata.

3. Set the proxy configuration to containerd, sandbox-image, and kubelet.
   Note: Sandbox-image is the service unit that pulls the sandbox image for containerd.

4. Describe your userdata with the following fields:

   MIME-Version: 1.0
   Content-Type: multipart/mixed; boundary="==BOUNDARY=="
   
   --==BOUNDARY==
   Content-Type: text/cloud-boothook; charset="us-ascii"
   
   #Set the proxy hostname and port
   PROXY=XXXXXXX:3128
   TOKEN=`curl -X PUT "http://169.254.169.254/latest/api/token" -H "X-aws-ec2-metadata-token-ttl-seconds: 21600"`
   MAC=$(curl -H "X-aws-ec2-metadata-token: $TOKEN" -v -s http://169.254.169.254/latest/meta-data/mac/)
   VPC_CIDR=$(curl -H "X-aws-ec2-metadata-token: $TOKEN" -v -s http://169.254.169.254/latest/meta-data/network/interfaces/macs/$MAC/vpc-ipv4-cidr-blocks | xargs | tr ' ' ',')
   
   #Create the containerd and sandbox-image systemd directory
   mkdir -p /etc/systemd/system/containerd.service.d
   mkdir -p /etc/systemd/system/sandbox-image.service.d
   
   #[Option] Configure yum to use the proxy
   cloud-init-per instance yum_proxy_config cat << EOF >> /etc/yum.conf
   proxy=http://$PROXY
   EOF
   
   #Set the proxy for future processes, and use as an include file
   cloud-init-per instance proxy_config cat << EOF >> /etc/environment
   http_proxy=http://$PROXY
   https_proxy=http://$PROXY
   HTTP_PROXY=http://$PROXY
   HTTPS_PROXY=http://$PROXY
   no_proxy=$VPC_CIDR,localhost,127.0.0.1,169.254.169.254,.internal,.eks.amazonaws.com
   NO_PROXY=$VPC_CIDR,localhost,127.0.0.1,169.254.169.254,.internal,.eks.amazonaws.com
   EOF
   
   #Configure Containerd with the proxy
   cloud-init-per instance containerd_proxy_config tee <<EOF /etc/systemd/system/containerd.service.d/http-proxy.conf >/dev/null
   [Service]    
   EnvironmentFile=/etc/environment
   EOF
   
   #Configure sandbox-image with the proxy
   cloud-init-per instance sandbox-image_proxy_config tee <<EOF /etc/systemd/system/sandbox-image.service.d/http-proxy.conf >/dev/null
   [Service]    
   EnvironmentFile=/etc/environment
   EOF
   
   #Configure the kubelet with the proxy
   cloud-init-per instance kubelet_proxy_config tee <<EOF /etc/systemd/system/kubelet.service.d/proxy.conf >/dev/null
   [Service]
   EnvironmentFile=/etc/environment
   EOF
   
   cloud-init-per instance reload_daemon systemctl daemon-reload 
   
   --==BOUNDARY==
   Content-Type:text/x-shellscript; charset="us-ascii"
   
   #!/bin/bash
   set -o xtrace
   
   #Set the proxy variables before running the bootstrap.sh script
   set -a
   source /etc/environment
   
   #Run the bootstrap.sh script
   B64_CLUSTER_CA=YOUR_CLUSTER_CA
   API_SERVER_URL=API_SERVER_ENDPOINT
   
   /etc/eks/bootstrap.sh EKS_CLUSTER_NAME --b64-cluster-ca $B64_CLUSTER_CA --apiserver-endpoint $API_SERVER_URL --container-runtime containerd
   
   --==BOUNDARY==--

   Note: Replace XXXXXXX:3128, YOUR_CLUSTER_CA, API_SERVER_ENDPOINT, and EKS_CLUSTER_NAME with your proxy, cluster certificate authority (CA), server endpoint, and cluster name. After you create the virtual private cloud (VPC) endpoints, add AWS service endpoints to NO_PROXY and no_proxy.

Configure the proxy setting for aws-node and kube-proxy

Note: If you route traffic from the cluster to the internet through an HTTP proxy and your EKS endpoint is public, then you must complete these steps. If you have a different configuration, then these steps are optional.

Create a ConfigMap to configure the environment values. Then, apply the ConfigMap in your cluster. Use the following script as an example for your ConfigMap:

apiVersion: v1
kind: ConfigMap

metadata:

   name: proxy-environment-variables

   namespace: kube-system

data:

   HTTP_PROXY: http://XXXXXXX:3128

   HTTPS_PROXY: http://XXXXXXX:3128

   NO_PROXY: KUBERNETES_SERVICE_CIDR_RANGE,localhost,127.0.0.1,VPC_CIDR_RANGE,169.254.169.254,.internal

Note: Replace KUBERNETES_SERVICE_CIDR_RANGE and VPC_CIDR_RANGE with the values for your CIDR ranges. After you create the VPC endpoints, add AWS service endpoints to NO_PROXY and no_proxy.

Then, set your HTTP proxy configuration to aws-node and kube-proxy:

$ kubectl patch -n kube-system -p '{ "spec": {"template":{ "spec": { "containers": [ { "name": "aws-node", "envFrom": [ { "configMapRef": {"name": "proxy-environment-variables"} } ] } ] } } } }' daemonset aws-node
$ kubectl patch -n kube-system -p '{ "spec": {"template":{ "spec": { "containers": [ { "name": "kube-proxy", "envFrom": [ { "configMapRef": {"name": "proxy-environment-variables"} } ] } ] } } } }' daemonset kube-proxy 

Create a managed node group

Create a new managed node group that uses the custom launch template that you created.

Test your proxy

To check the status of your nodes, run the following commands:

$ kubectl get nodes
            
$ kubectl run test-pod --image=amazonlinux:2 --restart=Never -- sleep 300
        
$ kubectl get pods -A

You receive an output that's similar to the following example:

$ kubectl get nodes -o wide
NAME                                                 STATUS   ROLES    AGE     VERSION                INTERNAL-IP       EXTERNAL-IP   OS-IMAGE         KERNEL-VERSION                 CONTAINER-RUNTIME

ip-192-168-100-114.ap-northeast-1.compute.internal   Ready    <none>   2m27s   v1.23.13-eks-fb459a0   192.168.100.114   <none>        Amazon Linux 2   5.4.219-126.411.amzn2.x86_64   containerd://1.6.6



$ kubectl run test-pod --image=amazonlinux:2 --restart=Never -- sleep 300

pod/test-pod created



$ kubectl get pods -A

NAMESPACE     NAME                       READY   STATUS    RESTARTS   AGE

default       test-pod                   1/1     Running   0          14s

kube-system   aws-node-cpjcl             1/1     Running   0          3m34s

kube-system   coredns-69cfddc4b4-c7rpd   1/1     Running   0          26m

kube-system   coredns-69cfddc4b4-z5jxq   1/1     Running   0          26m

kube-system   kube-proxy-g2f4g           1/1     Running   0          3m34s

Check your proxy log for additional information on your nodes' connectivity:

192.168.100.114 TCP_TUNNEL/200 6230 CONNECT registry-1.docker.io:443 - HIER_DIRECT/XX.XX.XX.XX -
192.168.100.114 TCP_TUNNEL/200 10359 CONNECT auth.docker.io:443 - HIER_DIRECT/XX.XX.XX.XX -
192.168.100.114 TCP_TUNNEL/200 6633 CONNECT registry-1.docker.io:443 - HIER_DIRECT/XX.XX.XX.XX -
192.168.100.114 TCP_TUNNEL/200 10353 CONNECT auth.docker.io:443 - HIER_DIRECT/XX.XX.XX.XX -
192.168.100.114 TCP_TUNNEL/200 8767 CONNECT registry-1.docker.io:443 - HIER_DIRECT/XX.XX.XX.XX -

Related information

How do I provide access to other IAM users and roles after cluster creation in Amazon EKS?