Merge pull request #67490 from mborsz/hollow2

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Kubemark: don't recreate hollow node on VM reboot.

**What this PR does / why we need it**:

This PR adds a toleration to run on unreachable node for 15 minutes in case of hollow nodes.
This is needed for https://github.com/kubernetes/kubernetes/issues/67120 where we saw that a VM reboot was triggering a storm of recreating hollow nodes.

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Needed for https://github.com/kubernetes/kubernetes/issues/67120

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```
/assign @shyamjvs

test/kubemark/resources/hollow-node_template.yaml

@@ -121,3 +121,12 @@ spec:
             memory: 20Mi
         securityContext:
           privileged: true
+      # Keep the pod running on unreachable node for 15 minutes.
+      # This time should be sufficient for a VM reboot and should
+      # avoid recreating a new hollow node.
+      # See https://github.com/kubernetes/kubernetes/issues/67120 for context.
+      tolerations:
+      - key: "node.kubernetes.io/unreachable"
+        operator: "Exists"
+        effect: "NoExecute"
+        tolerationSeconds: 900