Occasionally, multipathd does not update the path status of DM-Multipath devices after running I/O faults.
Set both HOTPLUG_USE_HWSCAN and HOTPLUG_USE_SUBFS to no in the /etc/sysconfig/hotplug file.
Multipathd fails occasionally because it fails to start "event checker" for some of the DM-Multipath devices. Because of this failure, multipathd is unable to keep track of the path up or down status for those devices.