Rescan syncs etcd and NDM.

Start starts registration of probes present in RegisteredProbes.

AttachEA is attach disk event name.

ChangeEA event is generated whenever some property of the blockdevice changes in udev.

DetachEA is detach disk event name.

RegisteredProbes contains register function of probes which we want to register.

ProbeEvent struct contain a copy of controller it will update disk resources.

EventAction action type for disk events like attach or detach events.