text: Title: Running pod and CronJob pod with shared iSCSI PVC not scheduled on same node
  Body: /kind bug
  
  ### **What happened**:
  
  A pod created by a cronjob and an existing pod which shared the same iSCSI pvc did not get scheduled on the same worker node. Because iSCSI can only be mounted read/write to one worker node, the pod scheduled by the cronjob became stuck in ContainerCreating.
  
  ### **What you expected to happen**:
  
  Because the two pods shared the same iSCSI pvc, the scheduler should have scheduled them on the same worker node to avoid conflicts. From [Oracle's documentation...](https://docs.oracle.com/cd/E52668_01/E88884/html/kubernetes-gsg-persistentvolume-iscsi.html)
  
  > Note that with iSCSI, support for both read and write operations limit you to hosting all of your pods on a single node. **The scheduler automatically ensures that pods with the same PersistentVolumeClaim run on the same worker node.**
  
  ### **How to reproduce it (as minimally and precisely as possible)**:
  >Before
  ```
  $ kubectl get pods -n debian-mirror -o wide
  NAME      READY     STATUS    RESTARTS   AGE       IP          NODE
  web-pod   1/1       Running   0          12d       10.2.0.86   kwork1.<REDACTED>
  
  $ kubectl get cronjobs -n debian-mirror
  NAME                    SCHEDULE       SUSPEND   ACTIVE    LAST SCHEDULE   AGE
  debian-mirror-updater   */15 * * * *   False     0         <none>          59s
  ```
  >After (pods on different nodes, stuck in ContainerCreating)
  ```
  $ kubectl get pods -n debian-mirror -o wide
  NAME                                     READY     STATUS              RESTARTS   AGE       IP          NODE
  debian-mirror-updater-1533744000-8qqj4   0/1       ContainerCreating   0          1m        <none>      kwork3.<REDACTED>
  web-pod                                  1/1       Running             0          12d       10.2.0.86   kwork1.<REDACTED>
  ```
  >Sharing the same pvc
  ```
  $ kubectl describe pod/web-pod -n debian-mirror | grep Volumes -A 4
  Volumes:
    debian-mirror-data:
      Type:       PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)
      ClaimName:  debian-mirror-pvc
      ReadOnly:   false
  $ kubectl describe pod/debian-mirror-updater-1533744000-8qqj4 -n debian-mirror | grep Volumes -A 4
  Volumes:
    debian-mirror-data:
      Type:       PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)
      ClaimName:  debian-mirror-pvc
      ReadOnly:   false
  $ kubectl get pvc -n debian-mirror
  NAME                STATUS    VOLUME            CAPACITY   ACCESS MODES   STORAGECLASS   AGE
  debian-mirror-pvc   Bound     large-storage-2   1500Gi     RWO                           21d
  ```
  
  ### **Anything else we need to know?**:
  
  **Environment**:
  - Kubernetes version (use `kubectl version`):
  ```
  $ kubectl version
  Client Version: version.Info{Major:"1", Minor:"11", GitVersion:"v1.11.1", GitCommit:"b1b29978270dc22fecc592ac55d903350454310a", GitTreeState:"clean", BuildDate:"2018-07-17T18:53:20Z", GoVersion:"go1.10.3", Compiler:"gc", Platform:"linux/amd64"}
  Server Version: version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.3", GitCommit:"2bba0127d85d5a46ab4b778548be28623b32d0b0", GitTreeState:"clean", BuildDate:"2018-05-21T09:05:37Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}
  ```
  - Cloud provider or hardware configuration:
  [Bare-metal Typhoon kubernetes](https://typhoon.psdn.io/cl/bare-metal/), 3 controller nodes and 4 worker nodes
  ```
  $ kubectl get nodes
  NAME           STATUS    ROLES               AGE       VERSION
  <REDACTED>     Ready     controller,master   60d       v1.10.3
  <REDACTED>     Ready     controller,master   60d       v1.10.3
  <REDACTED>     Ready     controller,master   60d       v1.10.3
  <REDACTED>     Ready     node                60d       v1.10.3
  <REDACTED>     Ready     node                60d       v1.10.3
  <REDACTED>     Ready     node                60d       v1.10.3
  <REDACTED>     Ready     node                60d       v1.10.3
  ```
  - Install tools:
  [Typhoon bare-metal installation guide (terraform)](https://typhoon.psdn.io/cl/bare-metal/)
  