k8s-gen-config.sh

# create kubeconfig for Kubelet:
KUBECONFIG_CONTENTS=$(echo "apiVersion: v1
kind: Config
users:
- name: kubelet
clusters:
- name: kubemark
  cluster:
    insecure-skip-tls-verify: true
    server: http://172.17.0.1:8080
contexts:
- context:
    cluster: kubemark
    user: kubelet
  name: kubemark-context
current-context: kubemark-context" | base64 | tr -d "\n\r")


KUBECONFIG_SECRET="./k8s-secret.json"
cat > "${KUBECONFIG_SECRET}" << EOF
{
  "apiVersion": "v1",
  "kind": "Secret",
  "metadata": {
    "name": "kubeconfig"
  },
  "type": "Opaque",
  "data": {
    "kubeconfig": "${KUBECONFIG_CONTENTS}"
  }
}
EOF


NODE_CONFIGMAP="./k8s-node-config.json"
cat > "${NODE_CONFIGMAP}" << EOF
{
  "apiVersion": "v1",
  "kind": "ConfigMap",
  "metadata": {
    "name": "node-configmap"
  },
  "data": {
    "content.type": ""
  }
}
EOF

k8s-hollow-node.json

{
	"kind": "ReplicationController",
	"apiVersion": "v1",
	"metadata": {
		"name": "hollow-node",
		"labels": {
			"name": "hollow-node"
		}
	},
	"spec": {
		"replicas": 1,
		"selector": {
			"name": "hollow-node"
		},
		"template": {
		  "metadata": {
				"labels": {
					"name": "hollow-node"
				}
			},
			"spec": {
				"volumes": [
					{
						"name": "kubeconfig-volume",
						"secret": {
							"secretName": "kubeconfig"
						}
					}
				],
				"containers": [
				{
					"name": "hollow-kubelet",
					"image": "kubemark:latest",
					"ports": [
						{"containerPort": 4194},
						{"containerPort": 10250},
						{"containerPort": 10255}
					],
					"env": [
						{
							"name": "CONTENT_TYPE",
							"valueFrom": {
								"configMapKeyRef": {
									"name": "node-configmap",
									"key": "content.type"
								}
							}
						}
					],
					"command": [
						"./kubemark.sh"
					],
					"args": [
						"--v=3",
						"--morph=kubelet",
						"$(CONTENT_TYPE)"
					],
					"volumeMounts": [
						{
							"name": "kubeconfig-volume",
							"mountPath": "/kubeconfig"
						}
					],
					"resources": {
						"requests": {
							"cpu": "50m",
							"memory": "100M"
						}
					},
					"imagePullPolicy": "Never"

				},
				{
					"name": "hollow-proxy",
					"image": "kubemark:latest",
					"env": [
						{
							"name": "CONTENT_TYPE",
							"valueFrom": {
								"configMapKeyRef": {
									"name": "node-configmap",
									"key": "content.type"
								}
							}
						}
					],
					"command": [
						"./kubemark.sh"
					],
					"args": [
						"--v=3",
						"--morph=proxy",
						"$(CONTENT_TYPE)"
					],
					"volumeMounts": [
						{
							"name": "kubeconfig-volume",
							"mountPath": "/kubeconfig"
						}
					],
					"resources": {
						"requests": {
							"cpu": "20m",
							"memory": "100M"
						}
					},
					"imagePullPolicy": "Never"
				}]
			}
		}
	}
}

Steps to run kubemark locally

- $KUBE_SRC below refers to the path of the kubernetes source code
  - commit 1cce15659750d90064882738425115ec547c1634

- build using $KUBE_SRC/hack/build-go
  - output is stored in $KUBE_SRC/_output/...

- kubemark:latest image is built by running "docker build -t kubemark:latest ." inside $KUBE_SRC/cluster/images/kubemark
  - need to copy kubemark binary into $KUBE_SRC/cluster/images/kubemark

- hollow-node.json is taken from template in $KUBE_SRC/test/kubemark/resources/
  - hardcode replicas
  - use kubemark:latest image instead of gcr.io version
  - added imagePullPolicy: Never to use locally built image (kubemark:latest)
  
- master is started by running: API_HOST=0.0.0.0 $KUBE_SRC/hack/local-up-cluster.sh
  - API_HOST=0.0.0.0 is needed so that hollow-kubelet can reach apiserver
  - modify ADMISSION_CONTROL line in start_apiserver by removing ServiceAccount
    - ServiceAccount admission controller adds a volume to the test pods. The volume cannot be mounted by the hollow-node kubelet.
  
- run gen_kubeconfig.sh to generate files used below
  
- hollow-kubelet is started by running:

  kubectl create -f $KUBE_SRC/test/kubemark/resources/kubemark-ns.json
  kubectl create -f ./k8s-secret.json --namespace=kubemark
  kubectl create -f ./k8s-node-config.json --namespace=kubemark
  kubectl create -f ./k8s-hollow-node.json --namespace=kubemark
  
- run kubectl cordon 127.0.0.1 to stop pods from being scheduled to default kubelet started by $KUBE_SRC/hack/local-up-cluster.sh