You can use Apsara File Storage NAS (NAS) volumes in Container Service for Kubernetes (ACK) clusters. This topic describes the features, types, use scenarios, limits, and billing rules of NAS volumes.
Description
Apsara File Storage NAS is a cloud service that provides a file storage solution for compute nodes. The compute nodes include Elastic Compute Service (ECS) instances, Elastic High-Performance Computing (E-HPC) instances, and Container Service for Kubernetes (ACK) clusters. NAS is a distributed file storage solution that provides shared access, scalability, high reliability, and high performance.
NAS uses Portable Operating System Interface of UNIX (POSIX)-based APIs and is compatible with native operating systems. NAS provides shared access, ensures data consistency, and implements mutual exclusion by using locks. NAS provides scalable file systems and allows simultaneous access to a NAS file system from multiple ECS instances. The storage capacity of a NAS file system automatically scales in or out when you add or remove files. NAS provides shared data sources for workloads and applications that run on multiple ECS instances or servers.
Storage types
NAS provides the following file system types: General-purpose NAS Capacity, General-purpose NAS Performance, and Extreme NAS. For more information, see NAS types.
Scenarios
The following table describes the operations that you can perform on a NAS volume to meet your business requirements.
Business requirement | References |
Use CNFS to manage NAS file systems (recommended) | You can use Container Network File System (CNFS) to manage the lifecycles of Apsara File Storage NAS (NAS) file systems. This ensures data security, enables data sharing, and accelerates access to NAS file systems. CFNS provides distributed caching services that support multiple parallel connections, allow you to read and write data cache at the client side, and support the Lease mechanism. These features can accelerate read and write operations for NAS file systems. This way, NAS file systems can provide a user experience similar to local file systems. For more information, see the following topics: |
Use CNFS to persist application data (recommended) | For more information, see the following topics: |
Use CNFS to automatically expand NAS volumes | You can configure expansion policies to automatically expand NAS volumes when the capacity usage exceeds a threshold. For more information, see Use CNFS to automatically expand NAS volumes. |
Accelerate data access in parallel computing scenarios | You can create distributed cache pools based on the memory of compute nodes. The cache pools can automatically scale in or out based on the computing demand to accelerate access to hot data in NAS volumes. We recommend that you use CNFS to accelerate data access in AI training and genomics computing scenarios. For more information, see Enable the distributed caching feature of the CNFS client. |
Persist application data without using CNFS | For more information, see the following topics: |
Set quotas for NAS volumes without using CNFS | You can set quotas on the directories of NAS volumes to manage the storage space of NAS volumes. For more information, see Expand a NAS volume. Note If your NAS file system is managed by using CNFS, no additional configuration is required. |
Limits
Apsara File Storage NAS is a shared storage service. A persistent volume claim (PVC) that is used to mount a NAS file system can be shared among pods.
You cannot use the Container Storage Interface (CSI) plug-in to mount Server Message Block (SMB) file systems.
We recommend that you use the NFSv3 file sharing protocol.
You can mount a NAS volume only to ECS instances in the same virtual private cloud (VPC) as the NAS file system.
General-purpose and Extreme NAS file systems have different limits on mounting scenarios, the number of file systems, and file sharing protocols. For more information about the supported states, see Limits.
Before you use NAS volumes, we recommend that you upgrade the CSI plug-in to the latest version.
After a mount target is created, wait until the state of the mount target changes to Available.
Do not delete the mount target before you unmount the NAS file system. Otherwise, the operating system hang error may occur.
Billing
For more information about the billing of NAS, see NAS billing overview.