Alibaba Cloud provides components that are developed based on the CSI Plugin and CSI-Provisioner of the Kubernetes community. The components allow self-managed Kubernetes clusters to use Alibaba Cloud storage services, including disks, File Storage NAS (NAS), and Object Storage Service (OSS).
Introduction to cloud storage
Alibaba Cloud provides low-cost, high-reliability, and high-availability storage services based on various storage resources, such as blocks, files, and objects. You can select suitable cloud storage services based on the storage requirements of your business load, and factors such as data volume, data access frequency, IOPS, and throughput. This section describes the commonly used Alibaba Cloud storage services.
Cloud disks
Cloud disks are block-level Elastic Block Storage (EBS) devices that use a distributed multi-replica mechanism to ensure low latency, high performance, high durability, and high reliability. You can create, release, and resize disks based on your business requirements. For more information, see Disks.
NAS
NAS is a distributed file system that supports both the Network File System (NFS) and Server Message Block (SMB) protocols and provides shared access, elastic scalability, high reliability, and high performance. For more information, see What is NAS?
OSS
OSS is a secure, cost-effective, and highly reliable Alibaba Cloud storage service that allows users to store large volumes of unstructured data, such as images, and audio and video data. For more information, see What is OSS?
The following table compares the services.
Item | Cloud disk | NAS | OSS |
Latency | Ultra-low latency (microseconds) | Low latency (milliseconds) | Low latency (tens of milliseconds) |
Throughput | Tens of gigabits per second | Hundreds of gigabits per second | Hundreds of gigabits per second |
Access mode | A single client performs random read and write operations on a disk by using Portable Operating System Interface of UNIX (POSIX). | Thousands of clients concurrently perform random read and write operations on a NAS file system by using POSIX. | Millions of clients concurrently access an OSS bucket and perform append operations by using the web. |
Mounting method | Disks cannot be shared. A disk can be mounted only to a single pod. | NAS file system can be shared. A NAS file system can be mounted to multiple pods. | OSS buckets can be shared. An OSS bucket can be mounted to multiple pods. |
For more information, see Alibaba Cloud storage service selection.