You can separately create a pay-as-you-go disk and manually attach the disk to an Elastic Compute Service (ECS) instance as a data disk.


  • The disk resides within the same zone as the instance to which you want to attach the disk.
  • The instance is in the Running (Running) or Stopped (Stopped) state and is not in the Locked (Locked) state.
  • The disk is in the Unattached (Available) state.
  • You have no overdue payments within your Alibaba Cloud account.


Before you attach a disk, take note of the following items:
  • Disks that are created along with instances and subscription data disks that are created for subscription instances are automatically attached to the corresponding instances.
  • A maximum of 64 data disks can be attached to an ECS instance. The maximum number of disks that can be attached to an instance varies with instance types. For more information, see Instance family.
    Note You can attach one system disk and a maximum of 16 data disks to an instance when you create the instance. If the instance requires more data disks, attach more data disks after the instance is created.
  • Disks that do not support the multi-attach feature and that have the multi-attach feature disabled can be attached only to a single instance at a time. Disks that support the multi-attach feature can be attached to multiple instances at a time. For more information, see Overview of disks that support NVMe.
Note The attach operation refers to the process of attaching disks to ECS instances in the ECS console, instead of mounting file systems in the operating systems of ECS instances by running the mount command. For information about how to format data disks and mount file systems, see Partition and format a data disk on a Linux instance and Partition and format a data disk on a Windows instance.

Attach a data disk

This section describes how to attach a data disk on the Instances page. You can also choose Storage & Snapshots > Disks in left-side navigation pane. Find the disk that you want to attach and choose More > Attach in the Actions column to attach the disk to an ECS instance.

  1. Log on to the ECS console.
  2. In the left-side navigation pane, choose Instances & Images > Instances.
  3. In the top navigation bar, select a region.
  4. Find the instance to which you want to attach disks and click the ID of the instance.
  5. Click the Cloud Disk tab. In the upper-left corner of the Cloud Disk tab, click Attach Disk.
  6. In the Attach Disk dialog box, configure parameters to attach a disk.
    1. Select the disk that you want to attach and specify the release settings for the disk.
      Parameter Description
      Disk Select the disk that you want to attach.
      Release Disk with Instance If you select this option, the disk is automatically released when the instance to which it is attached is released. If you do not select this option, the disk is retained when the instance to which it is attached is released.
      Note If the disk that you want to attach was detached from another instance on which it was previously used as the system disk, the instance specified by Release Disk with Instance refers to the instance from which the disk was detached, not the current instance.
      Delete Automatic Snapshots While Releasing Disk If you select this option, automatic snapshots of the disk are released when the disk is released. To retain backup data, do not select this option.
    2. Click Attach.
    If the disk is attached, the state of the disk becomes In Use.
  7. Create partitions and file systems before you can use the disk.
    Note When the disk is attached to the instance but has no partitions or file systems, the disk is unusable on the instance. For example, you cannot view the mount information of the disk attached to a Linux instance by running the df -h command. Perform the following operations based on the disk status and the operating system of the instance.
    Disk status Operating system of the instance What to do next
    New empty disk Linux
    Windows Server
    Disk created from a snapshot Linux Log on to the instance and run the following command to mount the disk partitions that have file systems available:
    mount <Data disk partition> <Mount point>
    Notice If you want to attach a new disk to the ECS instance to which the disk from which the snapshot was created was attached, you must change the UUID of the new disk before you can attach it to the ECS instance. For more information, see Modify the UUID of a disk.
    Windows Server N/A