在 Amazon EKS 上构建安全的 AI Agent 沙箱

# 关联 OIDC Provider（IRSA 前置条件）
eksctl utils associate-iam-oidc-provider \
  --cluster ${CLUSTER_NAME} \
  --region ${REGION} \
  --approve
# 创建 Karpenter Controller IAM Policy
cat > /tmp/karpenter-policy.json << 'POLICY'
{
  "Version": "2012-10-17",
  "Statement": [{
    "Sid": "Karpenter",
    "Effect": "Allow",
    "Action": [
      "ec2:CreateFleet", "ec2:CreateLaunchTemplate", "ec2:CreateTags",
      "ec2:DeleteLaunchTemplate", "ec2:DescribeAvailabilityZones",
      "ec2:DescribeImages", "ec2:DescribeInstances", "ec2:DescribeInstanceTypeOfferings",
      "ec2:DescribeInstanceTypes", "ec2:DescribeLaunchTemplates",
      "ec2:DescribeSecurityGroups", "ec2:DescribeSpotPriceHistory",
      "ec2:DescribeSubnets", "ec2:RunInstances", "ec2:TerminateInstances",
      "iam:AddRoleToInstanceProfile", "iam:CreateInstanceProfile",
      "iam:DeleteInstanceProfile", "iam:GetInstanceProfile",
      "iam:ListInstanceProfiles", "iam:RemoveRoleFromInstanceProfile",
      "iam:TagInstanceProfile", "iam:PassRole",
      "pricing:GetProducts", "ssm:GetParameter",
      "eks:DescribeCluster", "sqs:*"
    ],
    "Resource": "*"
  }]
}
POLICY

aws iam create-policy \
  --policy-name "KarpenterControllerPolicy-${CLUSTER_NAME}" \
  --policy-document file:///tmp/karpenter-policy.json
# 创建 Karpenter IRSA
eksctl create iamserviceaccount \
  --cluster ${CLUSTER_NAME} \
  --region ${REGION} \
  --name karpenter \
  --namespace kube-system \
  --attach-policy-arn "arn:aws:iam::${AWS_ACCOUNT_ID}:policy/KarpenterControllerPolicy-${CLUSTER_NAME}" \
  --approve
# 节点角色
aws iam create-role \
  --role-name "KarpenterNodeRole-${CLUSTER_NAME}" \
  --assume-role-policy-document '{"Version":"2012-10-17","Statement":[{"Effect":"Allow","Principal":{"Service":"ec2.amazonaws.com"},"Action":"sts:AssumeRole"}]}'
for POLICY in AmazonEKSWorkerNodePolicy AmazonEKS_CNI_Policy \
  AmazonEC2ContainerRegistryReadOnly AmazonSSMManagedInstanceCore; do
  aws iam attach-role-policy \
    --role-name "KarpenterNodeRole-${CLUSTER_NAME}" \
    --policy-arn "arn:aws:iam::aws:policy/${POLICY}"
done
# 允许 Karpenter 节点加入集群
eksctl create iamidentitymapping \
  --cluster ${CLUSTER_NAME} \
  --region ${REGION} \
  --arn "arn:aws:iam::${AWS_ACCOUNT_ID}:role/KarpenterNodeRole-${CLUSTER_NAME}" \
  --username system:node:{{EC2PrivateDNSName}} \
  --group system:bootstrappers --group system:nodes
# 标记子网（供 EC2NodeClass 的 subnetSelectorTerms 发现）
for SUBNET_ID in $(aws eks describe-cluster --name ${CLUSTER_NAME} \
  --region ${REGION} --query 'cluster.resourcesVpcConfig.subnetIds' \
  --output text); do
  aws ec2 create-tags --resources ${SUBNET_ID} \
    --tags Key=karpenter.sh/discovery,Value=${CLUSTER_NAME} --region ${REGION}
done
# 标记集群安全组（供 EC2NodeClass 的 securityGroupSelectorTerms 发现）
# 注意：必须给安全组也打标签，否则 Karpenter 启动新节点时会因找不到匹配的安全组而失败
CLUSTER_SG=$(aws eks describe-cluster --name ${CLUSTER_NAME} \
  --region ${REGION} --query 'cluster.resourcesVpcConfig.clusterSecurityGroupId' \
  --output text)
aws ec2 create-tags --resources ${CLUSTER_SG} \
  --tags Key=karpenter.sh/discovery,Value=${CLUSTER_NAME} --region ${REGION}
# 处理 ServiceAccount 所有权（IRSA 已创建 SA，Helm 需要接管）
kubectl -n kube-system annotate serviceaccount karpenter \
  meta.helm.sh/release-name=karpenter \
  meta.helm.sh/release-namespace=kube-system --overwrite 2>/dev/null
kubectl -n kube-system label serviceaccount karpenter \
  app.kubernetes.io/managed-by=Helm --overwrite 2>/dev/null
# 安装 Karpenter
helm upgrade --install karpenter oci://public.ecr.aws/karpenter/karpenter \
  --namespace kube-system \
  --version ${KARPENTER_VERSION} \
  --set "settings.clusterName=${CLUSTER_NAME}" \
  --set replicas=1 \
  --wait --timeout 120s

cat <<EOF | kubectl apply -f -
apiVersion: karpenter.k8s.aws/v1
kind: EC2NodeClass
metadata:
  name: kata-metal
spec:
  role: "KarpenterNodeRole-${CLUSTER_NAME}"
  amiSelectorTerms:
    - alias: al2023@latest
  subnetSelectorTerms:
    - tags:
        karpenter.sh/discovery: "${CLUSTER_NAME}"
  securityGroupSelectorTerms:
    - tags:
        karpenter.sh/discovery: "${CLUSTER_NAME}"
  blockDeviceMappings:
    - deviceName: /dev/xvda
      ebs:
        volumeSize: 100Gi
        volumeType: gp3
        deleteOnTermination: true
EOF

cat <<'EOF' | kubectl apply -f -
apiVersion: karpenter.sh/v1
kind: NodePool
metadata:
  name: kata-metal-burst
spec:
  template:
    metadata:
      labels:
        katacontainers.io/kata-runtime: "true"
        node-role: "kata-burst"
    spec:
      requirements:
        - key: node.kubernetes.io/instance-type
          operator: In
          values: ["c5.metal"]
        - key: karpenter.sh/capacity-type
          operator: In
          values: ["on-demand"]
      nodeClassRef:
        group: karpenter.k8s.aws
        kind: EC2NodeClass
        name: kata-metal
      expireAfter: 720h
  limits:
    cpu: "480"
  disruption:
    consolidationPolicy: WhenEmptyOrUnderutilized
    consolidateAfter: 30m
EOF

cat <<'EOF' | kubectl apply -f -
apiVersion: scheduling.k8s.io/v1
kind: PriorityClass
metadata:
  name: node-warm-placeholder
value: -1
globalDefault: false
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: node-warmer
  namespace: kube-system
spec:
  replicas: 1
  selector:
    matchLabels:
      app: node-warmer
  template:
    metadata:
      labels:
        app: node-warmer
    spec:
      priorityClassName: node-warm-placeholder
      terminationGracePeriodSeconds: 0
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: karpenter.sh/nodepool
                operator: Exists
      tolerations:
        - operator: Exists
      containers:
      - name: pause
        image: registry.k8s.io/pause:3.10.2
        resources:
          requests:
            cpu: "80"
            memory: "160Gi"
EOF