Elastic Compute Service:Create a disk from a snapshot

Procedure

1. Log on to the ECS console.

2. In the left-side navigation pane, choose Storage & Snapshots > Snapshots.

3. In the top navigation bar, select the region and resource group to which the resource belongs.

4. On the Snapshots page, click the Disk Snapshots tab.

5. Find the snapshot from which you want to create a cloud disk. In the Actions column, click Create Disk.

6. On the cloud disk buy page, configure the parameters. The following table describes the parameters.

   Parameter or section	Description
   Attach	Specify whether to attach the cloud disk that you want to create to an ECS instance. Not Attach: creates a cloud disk without attaching the disk to an ECS instance. If you select this option, you can create only pay-as-you-go cloud disks. The cloud disk and the ECS instance to which you want to attach the disk must reside in the same zone. After you create a cloud disk, you cannot change the region and zone of the disk. Exercise caution when you configure the Region and Zone parameters. Attach to ECS Instance: creates a cloud disk and attaches the disk to an ECS instance. If you select this option, you must select a region and select an ECS instance from the ECS Instance drop-down list.
   Billing Method	Specify the billing method of the cloud disk. Pay-as-you-go: A pay-as-you-go cloud disk can be attached to a subscription or pay-as-you-go ECS instance. Subscription: A subscription cloud disk can be attached only to a subscription ECS instance.
   Cloud Disk	The snapshot information is automatically populated. Select a disk category and specify a disk capacity. You must specify a disk capacity that is greater than or equal to the size of the snapshot. If the disk capacity that you specify is greater than the snapshot size, you must repartition the disk to ensure that the excess disk capacity can be used. Important If the snapshot is less than 2,048 GiB in size and you want to specify a disk capacity that is greater than 2,048 GiB, make sure that the source disk of the snapshot uses the GUID Partition Table (GPT) partition style. You can run the fdisk -lu command and then determine the partition style of a disk based on the value of the Disk label type parameter in the command output. If the parameter value is gpt, the disk uses the GPT partition style. If the source disk does not use the GPT partition style, we recommend that you specify a disk capacity that is less than 2,048 GiB to prevent data loss during partitioning. For more information, see Initialize a data disk whose size exceeds 2 TiB. For information about how to configure other parameters, such as the Multi-attach and Encryption parameters, see Create an empty data disk.

7. Confirm the configurations and costs and follow the on-screen instructions to complete the purchase.

   After a cloud disk is created, you can view the disk on the Cloud Disk tab. However, the cloud disk cannot be directly used on ECS instances.

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

   Scenario	What to do next
   You set the Attach parameter to Attach to ECS Instance when you create the cloud disk.	(Conditionally required) If the cloud disk created from a snapshot is attached to the Linux ECS instance to which the source disk of the snapshot is attached, the UUID of the new cloud disk conflicts with the UUID of the source disk. You must change the UUID of the new cloud disk. For more information, see Change the UUID of a disk. Mount partitions to the cloud disk or bring the disk online. Linux instance Connect to the ECS instance to which the cloud disk is attached and run the following command to mount a partition to the disk: sudo mount <Disk partition name> <Mount point> <Disk partition name>: Specify the name of the partition. Run the sudo fdisk -lu command to query the partition name. Example: /dev/vdc. <Mount point>: Specify an existing directory or run the sudo mkdir -p <New directory> command to create a new directory as the mount point. Example: sudo mkdir -p /data. Sample mount command: sudo mount /dev/vdc /data. Write the new partition information to the /etc/fstab file. This way, the partition is automatically mounted on system startup. For more information, see the Step 4: Configure the disk partition to automatically mount on instance startup section of the "Initialize a data disk whose size does not exceed 2 TiB on a Linux instance" topic. Windows instance Connect to the ECS instance to which the cloud disk is attached, click the icon, and then select Disk Management. Find the cloud disk that you want to manage, right-click a blank area, and select Online.
   You set the Attach parameter to Not Attach when you create the cloud disk.	Attach and initialize the cloud disk. For more information, see Attach a data disk.