Process for migrating Red Hat Spacewalk from RHN Classic to RHSM.

How do i migrate my Spacewalk from RHN to RHSM ? I found the following steps in the previous discussion. My Spacewalk is running on RHEL 6.8

# yum install subscription-manager-migration subscription-manager-migration-data

# rhn-migrate-classic-to-rhsm

Also, if the above steps are correct, do I have to run those commands on each and every RHEL 6.8 systems which are currently subscribed to RHN?