What Is CBS
Cloud Block Storage (CBS) is a block storage device with high availability, high reliability, high performance, low cost and customization, which can be used as an independent and scalable hard disk of Cloud Virtual Machine (CVM) to provide efficient and reliable storage for CVM instances. CBS provides persistent storage at the data block level. It is usually used as the main storage device for data (such as file system and database) that needs frequent and fine-grained updates, featuring high availability, high reliability and high performance.
CBS supports triple replication and EC distributed mechanism, backing up your data on different physical machines to avoid data loss caused by single point of failure, thereby improving data reliability. You can easily purchase, adjust, and manage your cloud disk devices through the console and create storage space larger than a single cloud disk capacity by building a file system.
According to different types of lifecycle, cloud disks can be divided into:
- Non-elastic cloud disk: Its lifecycle completely follows that of Cloud Virtual Machine. And it is purchased together with the Cloud Virtual Machine and used as a system disk, while it cannot be mounted and unmounted.
- Elastic cloud disk: Its lifecycle is independent of the Cloud Virtual Machine. It can be purchased separately and manually mounted to the Cloud Virtual Machine, or purchased together with the Cloud Virtual Machine and automatically mounted to the Cloud Virtual Machine as a data disk. Elastic cloud disk can be mounted or unmounted on the Cloud Virtual Machine in the same availability zone at any time. You can mount multiple elastic cloud disks to the same Cloud Virtual Machine, or you can unmount the elastic cloud disk from Cloud Virtual Machine A and then mount it on Cloud Virtual Machine.
Typical Use Cases
- If the hard disk space of a CVM is insufficient during use, you can purchase one or more cloud disks and mount to the CVM to meet the storage capacity requirements.
- No additional storage space is required when you purchase a CVM. When there is a need for storage, you can purchase a cloud disk to scale out the storage capacity of the CVM.
- When there is a demand for data exchange between multiple CVMs, you can unmount the cloud disk (data disk) and remount it to other CVMs.
- You can purchase multiple cloud disks and configure logical volume of LVM (Logical Volume Manager) to reach the upper limit of storage capacity of a single cloud disk.
- You can purchase multiple cloud disks and configure the RAID (Redundant Array of Independent Disks) policy to reach the upper limit of I/O capacity of a single cloud disk.
Product Features
The cloud platform provides diversified persistent storage devices. Users can flexibly select the type of hard disk, and store files and build databases on the hard disk.
- Hard Drive Selection: Premium Cloud Disk and SSD.
- Elastic mounting and unmounting: All types of elastic cloud disk support elastic mounting and unmounting. Multiple cloud disks can be mounted on the Cloud Virtual Machine to build a large-capacity file system.
- Elastic scale-out: You can scale out the cloud disk at any time, and a single disk supports a maximum of 32TB.
- Snapshot backup: It supports snapshot creation and rollback to back up key data. It also supports using snapshots to create hard disks for rapid service deployment.