The --host-volumes-dir flag on 'oc cluster up' allows the end user to specify where to place transient secret and configmap volumes that openshift uses for running pods. Because cluster up runs a containerized node, the directory needs to be mounted on the origin container as a shared volume mount so that mounts created by the node inside the origin container are visible to pod containers run by the node. If using Docker for Windows or Docker for Mac, the Docker daemon runs inside a VM. For it to be able to create a shared mount for the volumes directory, the directory cannot be located on a file system mounted from the host Windows or Mac machine.
Specifying a --host-voumes-dir that points to a directory on the Mac or Windows machine will result in cluster up failing to start.
Workaround (if any):
Specify a directory that is not mounted from the Mac or Windows machine. The use of this flag is limited in usefulness in these systems, because the data contained in this directory is transient and does not need to be kept across restarts.