Alibaba Cloud Block Storage is a block-level data storage service attached to Elastic Compute Service (ECS) instances and features low latency, persistence, and high reliability. Block Storage enables automatic replication within the same zone to avoid data loss caused by hardware failures and guarantee the stability and continuity of your workloads. You can manage Block Storage as you manage disks. For example, you can partition Block Storage devices that are attached to ECS instances and create file systems for Block Storage devices. You can also use Block Storage devices to achieve data persistence. Features Online Scaling Scales out disks without service disruption. You do not need to restart ECS instances or detach disks during scaling. Data Protection Creates snapshots for disks to support data protection, data recovery, image customization, and application disaster recovery. Data Encryption Supports data encryption and eliminates the need for users to build or maintain individual key management systems. I/O Isolation Enables storage input/output (I/O) isolation for enterprise-level instances. The connection between each ECS instance and all associated disks is assigned dedicated bandwidth. This feature bypasses storage I/O contention among different ECS instances and guarantees stable and consistent storage I/O performance.