3.2. Unmounting a Hierarchy
/etc/cgconfig.confconfiguration file, you can unmount it simply by removing the configuration directive from the mount section of this configuration file. Then restart the service to apply the new configuration.
umountto remove only hierarchies that you mounted yourself manually. Detaching a hierarchy that contains a default controller (listed in Available Controllers in Red Hat Enterprise Linux 7) will most probably lead to complications requiring a system reboot.