Sky Cloud  Block Storage  provides a persistent block storage service for CVM instances. CBS automatically stores data in multiple redundant copies in an availability zone to eliminate the risk of single points of data failure, providing up to 99.9999999% data reliability. CBS offers cloud disks in multiple types and specifications to achieve stable and low-latency storage performance. CBS can be mounted to or unmounted from instances in the same availability zone, and its storage capacity can be altered in a few minutes, meeting elastic storage requirements. Payment is based on actual usage, and allowing you to enjoy all the above features at a low price point.