The dlm is configured and controlled from user space through sysfs and a couple of ioctl's. A command line program, dlm_tool, can be used to do everything manually.
Here are the dlm_tool config/control actions that will be used:
So, dlm_tool is standing in for what would usually be two different entities. The first set of config/control actions would usually be performed by a system daemon associated with a cluster membership manager. The second set of libdlm actions would usually be performed by an application that wants to use the dlm for synchronization.