Multiple choices, which of the following descriptions of the Huawei Oceanstor 9000 product system is...

MDS service is responsible for managing the metadata of the file system

DS service is responsible for storing the file data of the system, but not the storage of metadata

CMS service is responsible for device management of the physical nodes of the cluster Some nodes in D. system are responsible for providing MDS services, and some nodes are responsible for providing DS services