An Internet company purchased a batch of TaiShan servers to expand the original distributed storage Ceph. Which of the following are the main steps for installing and deploying block storage services? (Multiple choices)

An Internet company purchased a batch of TaiShan servers to expand the original distributed storage Ceph. Which of the following are the main steps for installing and deploying block storage services? (Multiple choices)
A . Mapping block device images
B . Create a block device
C . Create a file system
D . Create a storage pool

Answer: ABD