I'm playing with kubernetes and google container engine (GKE).

I deployed a container from this image jupyter/all-spark-notebook

This is my replication controller :

{
  "apiVersion": "v1",
  "kind": "ReplicationController",
  "metadata": {
    "name": "datalab-notebook"
  },
  "spec": {
    "replicas": 1,
    "selector": {
      "app": "datalab-notebook"
    },
    "template": {
      "metadata": {
        "name": "datalab-notebook",
        "labels": {
          "environment": "TEST",
          "app": "datalab-notebook"
        }
      },
      "spec": {
        "containers": [{
          "name": "datalab-notebook-container",
          "image": "jupyter/all-spark-notebook",
          "env": [],
          "ports": [{
            "containerPort": 8888,
            "name": "datalab-port"
          }],
          "volumeMounts": [{
            "name": "datalab-notebook-persistent-storage",
            "mountPath": "/home/jovyan/work"
          }]
        }],
        "volumes": [{
          "name": "datalab-notebook-persistent-storage",
          "gcePersistentDisk": {
            "pdName": "datalab-notebook-disk",
            "fsType": "ext4"
          }
        }]
      }
    }

  }
}

As you can see I mounted a Google Compute Engine Persistent Disk. My issue is that the container uses a non-root user and the mounted disk is owned by root. so my container can not write to the disk.

• Is there a way to mount GCE persistent disks and make them read/write for containers without non-root users?
• Another general question : is it safe to run container with root user in Google Container Engine?

Thank you in advance for your inputs

I ran into the same problem. The workaround I used was to run df -h on the host machine that the container was running on. From there I was able to find the bind point of the persistant storage. It should look something like /var/lib/kubelet/plugins/kubernetes.io/gce-pd/mounts/<pd-name>. It will also be one of the ones that has a file system that starts with /dev that isn't mounted to root.

Once you've found that you can run sudo chmod -R 0777 /var/lib/kubelet/plugins/kubernetes.io/gce-pd/mounts/<pd-name> from the host box, and now at least your container can use the directory, though the files will still be owned by root.