Cluster monitoring in OpenShift 3.x with database

I'm using advanced installation method to configure openshift 3.9 in my lab. I've had previous experience with kubernetes and I used heapster to monitor the cluster metrics which was accessible from its inbuilt InfluxDB database.

I've heard of hawkular, heapster and cassandra in openshift but after the installation these pods show 'ImagePullBackOff' error. Is there a simple way to monitor the cluster information like:

a) Pod memory usage
b) Pod CPU usage
c) Node CPU/Memory Usage

I need to store these data in a database and access it all together. Can anyone suggest any scheme as I might be missing some inbuilt feature.