Description of problem:
This bug is split from https://bugzilla.redhat.com/show_bug.cgi?id=1646886#c10
it is brought by the fix of bz 1646886
metrics failed at TASK [Mark node unschedulable]
********************************************************************************
TASK [Mark node unschedulable] 
task path: /usr/share/ansible/openshift-ansible/playbooks/openshift-node/private/restart.yml:11
Monday 10 June 2019  22:56:55 -0400 (0:00:01.261)       0:02:48.041 *********** 
fatal: [vm-10-0-77-163.hosted.upshift.rdu2.redhat.com]: FAILED! => {
    "msg": "The task includes an option with an undefined variable. The error was: 'l_kubelet_node_name' is undefined\n\nThe error appears to have been in '/usr/share/ansible/openshift-ansible/playbooks/openshift-node/private/restart.yml': line 11, column 5, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n  tasks:\n  - name: Mark node unschedulable\n    ^ here\n"
}
********************************************************************************

Actually the installation is not blocked, but the network diagram is empty on console UI in CRI-O env, still need to do workaround

# systemctl restart atomic-openshift-node.service

# oc get pod -n openshift-infra
NAME                            READY     STATUS      RESTARTS   AGE
hawkular-cassandra-1-9b48n      1/1       Running     0          10m
hawkular-metrics-schema-vqmjr   0/1       Completed   0          12m
hawkular-metrics-whpfz          1/1       Running     1          13m
heapster-sqlts                  1/1       Running     0          12m


Version-Release number of selected component (if applicable):
# rpm -qa | grep openshift-ansible
openshift-ansible-docs-3.11.119-1.git.0.c9a8ebf.el7.noarch
openshift-ansible-playbooks-3.11.119-1.git.0.c9a8ebf.el7.noarch
openshift-ansible-3.11.119-1.git.0.c9a8ebf.el7.noarch
openshift-ansible-roles-3.11.119-1.git.0.c9a8ebf.el7.noarch


How reproducible:
Always

Steps to Reproduce:
1. Install metrics 311, parameters see [Additional info] part
2.
3.

Actual results:
Install metrics failed at TASK [Mark node unschedulable]

Expected results:
Installation should be fine

Additional info:
openshift_metrics_install_metrics=true
openshift_metrics_cassandra_storage_type=dynamic