Create subscription or pay-as-you-go data disks to increase the storage space of ECS instances - Elastic Compute Service

You can create a new subscription or pay-as-you-go data disk and attach the disk to an Elastic Compute Service (ECS) instance to increase the storage space of the instance. This topic describes how to create a data disk.

Limits

The following table describes the limits that are imposed on cloud disks that use different billing methods.

Disk	Limits
Pay-as-you-go disk	For information about the pay-as-you-go billing method, see Pay-as-you-go.
Subscription disk	When you create a subscription disk, you must attach it to a subscription ECS instance. You cannot separately create subscription disks. You cannot separately detach or release subscription disks. Subscription disks expire and are released together with the ECS instances to which they are attached. If you want to release a subscription disk, you can convert it into a pay-as-you-go disk, and then detach and release the disk.

Disks are independent of each other. You cannot merge disks by formatting them. Before you create disks, we recommend that you determine the number and capacity of disks that you need based on your business requirements.

Procedure

Log on to the ECS console.
In the left-side navigation pane, choose Storage & Snapshots > Block Storage (Disks) .
In the upper-left corner of the Cloud Disk tab, click Create Cloud Disk.

On the cloud disk buy page that appears, configure the parameters described in the following table.

Parameter	Description
Attach	Specify whether to attach the cloud disks that you want to create to an ECS instance. Not Attach: creates cloud disks without attaching them to ECS instances. If you select Not Attach, only pay-as-you-go cloud disks can be created. The cloud disks and the ECS instances to which you want to attach the disks must reside in the same zone. Proceed with caution when you specify the Region and Zone parameter. Attach to ECS Instance: creates cloud disks and attaches the disks to a specific ECS instance that resides in the same zone as the disks. If you select Attach to ECS Instance, you must specify the ECS Instance parameter by selecting a destination region and an ECS instance.
Billing Method	Specify the billing method of the cloud disks. Pay-as-you-go: Pay-as-you-go disks can be attached to subscription or pay-as-you-go ECS instances. Subscription: Subscription disks must be attached to subscription ECS instances.
Storage	Select a disk category and specify the capacity per disk. Configure the following parameters based on your business requirements: Performance Level: You can specify performance levels for only Enterprise SSDs (ESSDs). You can select a performance level based on the capacity of an ESSD. The performance of an ESSD varies with the capacity and performance level of the ESSD. For more information, see ESSDs. Create from Snapshot: Select a snapshot to create cloud disks. After you configure this parameter, the created cloud disks contain data from the selected snapshot. For more information, see Create a disk from a snapshot. Multi-attach: You can select this option to enable the multi-attach feature for ESSDs. This way, you can attach each created ESSD to multiple ECS instances in the same zone. For more information, see Multi-attach for cloud disks. Disk Encryption: Disk encryption is applicable to scenarios that require data security and regulatory compliance. If you select this option, data stored on the created disks is automatically encrypted.
Quantity	Specify the number of cloud disks that you want to create. Important You can attach up to 64 data disks to an ECS instance. The number of cloud disks that can be attached to an instance varies based on the instance type. You can call the DescribeInstanceTypes operation to query the number of cloud disks that can be attached to an instance of an instance type. You have a zone-specific capacity quota for cloud disks. The total capacity of the cloud disks that you want to create is calculated by using the following formula and counts against the capacity quota: Capacity per cloud disk × Number of cloud disks that you want to create. After you select a disk category, the purchased capacity and the remaining capacity quota of the disk category are displayed on the cloud disk buy page. You can go to the Quota Center to view and adjust your disk capacity quotas.
Release	Specify whether to delete the automatic snapshots of the cloud disks when the disks are released or whether to release the cloud disks when the ECS instance to which they are attached is released. This parameter is available only if you set the Attach parameter to Attach to ECS Instance and the Billing Method parameter to Pay-as-you-go.
Terms of Service	Read and select ECS Terms of Service.
Others (Optional)	Specify the Name, Description, Tag, and Resource Group parameters to facilitate search and management.

Confirm the configurations and fees, click Preview, and then proceed as prompted to create the cloud disks.
After the cloud disk is created, you can view it on the Cloud Disk tab. However, the cloud disks cannot be directly used on ECS instances.

The following table describes the operations that you must perform before you can use the created cloud disks.

Scenario

What to do next

You set the Attach parameter to Attach to ECS Instance when you create the cloud disks.

Perform the following operations to initialize the cloud disks:

If the disks are larger than 2 TiB in size, perform the operations that are described in Initialize a data disk whose size exceeds 2 TiB.
If the disks are smaller than or equal to 2 TiB in size, perform the operations that are described in Initialize a data disk whose size does not exceed 2 TiB on a Linux instance or Initialize a data disk whose size does not exceed 2 TiB on a Windows instance.

You set the Attach parameter to Not Attach when you create the cloud disks.

Attach and initialize the disks. For more information, see Attach a data disk.