Regarding the NDMP2-Way backup method of OceanStor V3, which of the following descriptions is correct? (Multiple choice)

Regarding the NDMP2-Way backup method of OceanStor V3, which of the following descriptions is correct? (Multiple choice)
A . The NAS device sends backup data to its directly attached tape device via Fibre Channel
B . Tape devices can be shared by multiple NAS devices
C . The tape device must support the NAMP protocol
D . The backup server will generate an index to maintain these files and directories

Answer: ACD