File Storage NAS:FAQ about basic management features

What are the limits of NAS file systems?

• Each Alibaba Cloud account can create a maximum of 20 General-purpose NAS file systems and 200 Extreme NAS file systems in a region.

• The maximum capacity of a Capacity NAS file system is 10 PiB. The maximum capacity of a Performance NAS file system is 1 PiB. The maximum capacity of a Premium NAS file system is 1 PiB. The maximum capacity of an Extreme NAS file system is 256 TiB.

• A General-purpose NAS file system can contain a maximum of 1 billion files. An Extreme NAS file system can contain a maximum of 0.5 billion files.

For more information, see Limits.

Why is the "insufficient inventory" error returned when I create a file system?

This error occurs because no storage resources are available in the selected zone. We recommend that you create the file system in another zone.

What is a mount target? What are the features of a mount target?

A mount target is an endpoint that compute nodes, such as Elastic Compute Service (ECS) instances, Elastic High Performance Computing (E-HPC) clusters, or container service clusters, can use to access a NAS file system. When you create a mount target for a file system, you must select a network and a permission group. To access the file system using the mount target, a compute node must reside in the selected network and meet the rules specified in the permission group. Multiple compute nodes can use a mount target to access a NAS file system at the same time.

How do I calculate the number of mounted compute nodes?

If compute nodes are ECS instances, one ECS instance is counted as one compute node. If compute nodes are containers, one container is counted as one compute node.

Can I change the network type of a mount target?

No. After you create a mount target for a file system, you cannot change its network type. However, you can create a mount target with a different network type and use the new mount target to remount the file system.

For example, if you have created a Capacity NAS file system and mounted it using a classic network mount target, perform the following steps to replace the classic network mount target with a VPC mount target:

1. Create a mount target in a VPC. For more information, see Create a mount target.

2. Unmount the file system that was mounted using the classic network mount target. For more information, see Unmount file systems.

   Log on to the NAS console. On the Mount Targets tab of the target file system's details page, choose > Client List in the Actions column for the mount target. Make sure that the Client List is empty.

3. Mount the file system on the same destination path using the VPC mount target. For more information, see Mount a file system.

4. In the Actions column for the classic network mount target, choose the icon > Disable. Then, confirm the operation.

5. After you confirm that your business is not affected, choose > Delete, and then confirm the operation.

Can I switch VPCs for a NAS file system?

Only General-purpose NAS file systems support VPC switching. Extreme NAS file systems do not support VPC switching. Use one of the following methods to switch VPCs and remount a NAS file system:

• Directly add a mount target.

  If only one mount target exists, add a mount target whose network type is VPC and then mount the NAS file system.

• Delete an existing mount target and then create a mount target in another VPC.

  You can create a maximum of two mount targets for a General-purpose NAS file system. If the maximum number of mount targets is reached, you must delete an existing mount target and then create a mount target in another VPC.

  1. Unmount the file system that resides in the existing VPC. For more information, see Unmount a file system in the NAS console or Unmount a file system by running a command.

  2. Delete the existing mount target. For more information, see Delete a mount target.

  3. Create a mount target in another VPC. For more information, see Create a mount target.

  4. Mount the file system using the new mount target. For more information, see Scenarios.

How do I delete a mount target that is created by Cloud Shell?

When you use Cloud Shell to manage a NAS resource, Cloud Shell automatically creates a mount target in the mount target list of the NAS file system.

Use one of the following methods to delete the mount target created by Cloud Shell:

• Delete the mount target from the NAS file system

  1. Log on to the NAS console.

  2. In the left-side navigation pane, choose File System > File System List.

  3. In the top navigation bar, select the resource group and region where your file system resides.

  4. On the File System List page, select Delete in the Actions column for the target file system.

  5. In the Delete File System dialog box, find the mount target created by Cloud Shell and click Delete in the Actions column.

     Move the pointer over the icon to check whether the mount target is the one that you want to delete.

  6. In the Delete Mount Target dialog box, confirm the information and click OK to delete the mount target created by Cloud Shell.

  7. Click Cancel to close the Delete File System dialog box.

• Delete the mount target in Cloud Shell

  1. Log on to Cloud Shell.

  2. In the top menu bar, choose Unmount File Storage.

  3. In the Unmount Storage Space dialog box, confirm the file system ID to unmount.

     • If the mount target was created by the current RAM user, select Current User and click Unmount.

     • If another RAM user created the mount target, log on with your Alibaba Cloud account, select RAM User, and then click Unmount.

How do I delete a mount target that is created by Cloud Backup?

When you use Cloud Backup to back up a General-purpose NAS resource, Cloud Backup automatically creates a mount target in the General-purpose NAS file system.

Use one of the following methods to delete the mount target created by Cloud Backup:

• Delete the mount target from the NAS file system

  1. Log on to the NAS console.

  2. In the left-side navigation pane, choose File System > File System List.

  3. In the top navigation bar, select the resource group and region where your file system resides.

  4. On the File System List page, for the target file system, select Delete from the Actions column.

  5. In the Delete File System dialog box, locate the mount target created by Cloud Backup and click Delete in the Actions column.

     You can move the pointer over the icon to check whether the mount target is the one that you want to delete.

  6. In the Delete Mount Target dialog box, confirm the information and click OK to delete the Cloud Backup mount target.

  7. Click Cancel to close the Delete File System dialog box.

• Delete the mount target from the file backup entry

  1. Log on to the NAS console.

  2. In the left-side navigation pane, choose Data Service > File Backup (Cloud Backup Service).

  3. In the top navigation bar, select the resource group and region where your file system resides.

  4. On the File Backup page, click Manage Mounts.

  5. In the Manage Mounts panel, locate the destination file system and click Remove Mount Target.

  6. In the confirmation dialog box, click OK to delete the mount target created by the backup service.

How do I delete a mount target that is created by PAI?

When PAI uses a NAS file system as a dataset for data processing and modeling, PAI automatically creates a mount target for the NAS file system.

Perform the following steps to delete the mount target created by PAI:

1. Log on to the NAS console.

2. In the left-side navigation pane, choose File System > File System List.

3. In the top navigation bar, select the resource group and region where your file system resides.

4. On the File System List page, select Delete in the Actions column of the target file system.

5. In the Delete File System dialog box, find the mount target created by PAI and click Delete in the Actions column.

   Move the pointer over the icon to check whether the mount target is the one that you want to delete.

6. In the Delete Mount Target dialog box, confirm the information and click OK to delete the mount target created by PAI.

7. Click Cancel to close the Delete File System dialog box.

How can I view a list of clients on which a file system is mounted?

1. Log on to the NAS console.

2. In the left-side navigation pane, choose File System > File System List.

3. In the top navigation bar, select the resource group and region where your file system resides.

4. On the File System List page, click the destination file system ID. Then, click the Mount Targets tab.

5. In the Mount Target list, click Client List in the Actions column for the desired mount target.

   In the Client List dialog box, view the IP addresses of the clients on which the file system is mounted.

   Note

   The list includes only the clients that have accessed the NAS file system within the last minute. Clients that are mounted but not in use might not be displayed in the list.

Is the permission group associated with a file system deleted when I delete the file system?

No, it is not. When you delete a file system, the associated permission group and its rules are not deleted. However, the mount target is deleted. For more information about how to delete a permission group, see Manage permission groups.

Can NAS files be restored after they are deleted by mistake?

No.

To retrieve accidentally deleted data in a timely manner, we recommend that you enable the snapshot, recycle bin, or file backup feature. For more information, see Snapshots, Back up a General-purpose NAS file system, and Recycle bin.

Why am I unable to delete files in a file system after the file system is mounted?

This may be because the IP address that you use is denied access to the file system or your account does not have the required permissions. Make sure that the permission group grants read and write permissions and that you are logged on with the administrator account (Windows) or the root user account (Linux).

Why am I unable to create classic network mount targets?

As of November 21, 2022, you can no longer create classic network mount targets for General-purpose NAS file systems. However, classic network mount targets that were created before this date can still be used to access file systems.

Why am I unable to delete a file system?

This may be because you do not have the permissions to delete the file system.

If you are a RAM user, you must have full control over the file system to delete it. You cannot grant a RAM user permissions to view only a specific NAS file system. To grant a RAM user full control over a specific NAS file system, you must first grant the RAM user permissions to view all NAS file systems, and then grant the permissions to delete and modify the specific NAS file system. For more information, see Procedure for granting permissions to a RAM user and Example 1: Grant a RAM user permissions on a file system.

Why is the ENIRamRole.NotAuth error returned when I create a file system?

• Cause: The Default Service Authorization For Extreme NAS And CPFS (AliyunNASManageENIRole) has not been granted.

  The Default Service Authorization For Extreme NAS And CPFS (AliyunNASManageENIRole) service access authorization is not granted. When you use an Extreme NAS file system, the NAS file system must have access to resources in other cloud products, such as VPC and ECS. By default, NAS assumes the AliyunNASManageENIRole role to access your resources in other cloud products.

• Solution

  1. Log on to the NAS console.

  2. On the Overview page, in the References section on the right, click Authorization Management.

  3. On the Authorize Extreme NAS and CPFS card, click Authorize Now.

  4. On the RAM Quick Authorization page, confirm the role information and click Authorize.

Does a NAS file system still exist after the associated ECS instance is released?

Yes, it does. After the ECS instance on which a NAS file system is mounted is released, the NAS file system still exists and the data is not lost.

Why am I unable to create a NAS file system using the CSI plug-in and The specified AZone inventory is insufficient is returned?

Issue

The NAS file system cannot be created using the CSI plug-in. The following error message is returned:

ErrorCode: InvalidAZone.NotFound
Recommend:
RequestId: xxxxx
Message: The specified AZone inventory is insufficient.

Cause

The specified zone is invalid.

Solution

Specify another zone. Log on to OpenAPI and call the DescribeZones operation to retrieve all zones in your region and the NAS file system types supported in each zone.

You can also log on to the NAS console to create a file system. For more information, see Create a file system.

How do I quickly delete excessively large files stored in a file system?

Speed up the deletion process by running parallel rm -rf commands on multiple, non-nested subdirectories. For example, open several terminals, navigate to the NAS mount point (such as /mnt), and simultaneously delete directories like /mnt/dir1, /mnt/dir2, and /mnt/dir3. Do not attempt to simultaneously delete a parent directory and one of its subdirectories (such as /mnt/dir1 and /mnt/dir1/subdir).

What do I do if command execution is stuck in the mount directory of a deleted file system?

You must comment out the NAS configuration from the /etc/fstab file and then restart the server.

To prevent this issue from recurring, we recommend that you unmount the file system from the operating system before you delete it. If automatic mounting is enabled, you must also delete or modify the automatic mounting configuration to ensure that the file system is no longer automatically mounted at startup. For more information, see Unmount a file system in the NAS console, Unmount a file system by running a command, and Delete a file system.

Does Alibaba Cloud still store my data after my NAS file system is released?

No, it does not. The data is immediately deleted after you release a NAS resource. Alibaba Cloud does not retain deleted data. For more information, see the File Storage NAS Service Level Agreement.

If a General-purpose or Extreme NAS file system is suspended due to an overdue payment, it is retained for 15 days. If you do not settle the overdue payment within the retention period, Alibaba Cloud assumes that you no longer require NAS. Alibaba Cloud then terminates the NAS service terms and no longer provides related services. The data in your NAS file system is deleted and cannot be restored. For more information, see Overdue payments.

How do I view the throughput of an Extreme NAS file system?

1. Log on to the NAS console.

2. In the left-side navigation pane, choose File System > File System List.

3. In the top navigation bar, select a region.

4. On the File System List page, click the ID of the file system to query.

5. On the Basic Information tab, view the throughput of the file system based on the Maximum Capacity and Bandwidth parameters. For more information about the bandwidth of Extreme NAS file systems, see Performance metrics.