Traditional shared file systems lack precise control of storage resource quotas, recovery of accidentally deleted data, monitoring metrics about volume capacities and performance statistics, and encryption algorithms. In addition, the latency of reading or writing small-sized files is high. Container Service for Kubernetes (ACK) releases Container Network File System (CNFS) to improve the performance of Apsara File Storage NAS (NAS). This topic describes the features, storage types, use scenarios, limits, and billing of CNFS.


CNFS allows ACK to create, delete, describe, mount, monitor, and scale individual file stores of Alibaba Cloud by using Kubernetes CustomResourceDefinition (CRD) objects.

Feature Description
Recycle bin You can recover accidentally deleted files from the recycle bin.
Resource quotas Storage resource quotas. You can dynamically increase the quota limits. For more information about how to use the storage resource quotas, see Set quotas on the subdirectories of NAS volumes.
Volume monitoring This feature allows you to monitor the usage and I/O performance of volumes, including persistent volume claims (PVCs). For more information about how to use the volume monitoring feature, see Use csi-plugin to monitor storage resources at the node side.
Lifecycle management This feature allows you to manage full lifecycles of NAS file systems and Object Storage Service (OSS) buckets.
Resource protection The resource protection feature prevents users from accidentally deleting the entire file system.
Upgrades without service disruption Hot upgrades for volume drivers are supported.

Some advanced CNFS features, such as the recycle bin, resource quotas, and lifecycle management, can be configured only in the NAS console.

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.

Usage notes

  • CNFS simplifies the procedure of mounting NAS volumes. Compared with using PVCs, you do not need to frequently switch between the NAS console and ACK console when you use CNFS to mount a NAS volume. This reduces the operations to mount a NAS volume and improves the success rate of mounting a NAS volume. For more information, see Use CNFS to manage NAS file systems.
  • You can use expansion policies to enable auto expansion of NAS volumes when the capacity usage exceeds specific thresholds. For more information, see Use CNFS to automatically expand NAS volumes.
  • You can use the Container Storage Interface (CSI) plug-in provided by Alibaba Cloud to create multiple persistent volumes (PVs) that are used to mount the same NAS subdirectory. For more information, see Use CNFS to share a dynamically provisioned NAS volume.
  • You can use the recycle bin feature of CNFS to restore accidentally deleted files. For more information, see Use the recycle bin feature of CNFS to restore data.


For more information about the billing of NAS, see NAS billing overview.