Mounting separate disk for OpenShift 4 etcd

Issue

• How to mount a separate disk for etcd on OpenShift control plane nodes.
• How to mount a separate disk for /var/lib/etcd on OpenShift master nodes.
• Due to bad etcd disk performance, a separate disk for etcd is needed.
• Following the recommendations in etcd backend performance requirements for OpenShift, it's needed to configure a separate disk for etcd in our installed cluster.
• There is a way to separate /var/lib/containers to a different disk: Mounting separate disk for OpenShift 4 container storage. Is it possible to do the same with /var/lib/etcd?
• Bad etcd performance.