DMP opens the secondary (passive) paths with an exclusive flag in Active/Passive arrays. So, if you test the secondary (passive) raw paths of the disk, the vxfentsthdw command fails due to DMP's exclusive flag.

Recommended action: For Active/Passive arrays when you want to test the disks in raw format, you must use an active enabled path with the vxfentsthdw command. Run the vxdmpadm getsubpaths dmpnodename=enclosure-based_name command to list the active enabled paths.