Setting up Device Mapper

Using https://docs.docker.com/storage/storagedriver/device-mapper-driver/#manage-devicemapper as a guide. Perform the "Configure direct-lvm mode manually" steps. The daemon.json file needs to be a little different:

	{
		"storage-driver": "devicemapper",
		"storage-opts": [
		"dm.thinpooldev=/dev/mapper/docker-thinpool-tpool",
		"dm.use_deferred_removal=true",
		"dm.use_deferred_deletion=true"
		]
	}

Notice the "-tpool"