Creating an EVS Disk

Scenarios

You can use EVS disks as system disks or data disks for servers. You can create data disks on the EVS console, or create them together with system disks on the cloud server console.

This section describes how to create data disks on the EVS console.

Notes and Constraints

**Table 1** Constraints on creating disks
Create On	Description
EVS console	Disks created on the EVS console are data disks. You need to manually attach them to servers. Disks can only be attached to servers in the same region and AZ. Once created, the region and AZ cannot be changed. There are quantity and capacity quotas on EVS disks, so properly plan the number of disks and total disk capacity your workloads require. For details, see Managing EVS Quotas.
Cloud server console	System disks can only be created together with servers and are automatically attached. Data disks created together with servers or added after the server creation are automatically attached. Disks will have the same billing mode as their server if the disks are created together with the server. Disks created together with BMSs are SCSI disks.
-	Capacities of multiple disks cannot be combined, and the capacity of a single disk cannot be split.

Procedure

Log in to the console.
Click in the upper left corner and select the desired region and project.
Click in the upper left corner and choose Storage > Elastic Volume Service.

The Elastic Volume Service page is displayed.
In the upper right corner, click Create Disk.
- The following figure shows the parameter setting of non-encrypted disks.
  Figure 1 Non-encrypted disks
- The following figure shows the parameter setting of encrypted disks.
  Figure 2 Encrypted disks

Configure disk parameters according to Table 2.

**Table 2** Disk parameters
Parameter	Sub-Parameter	Description	Example Value
Region	-	Mandatory Resources are region-specific and cannot be used across regions through internal network connections. For low network latency and quick resource access, select the nearest region.	-
AZ	-	Mandatory The availability zone (AZ) where you want to create the disk. NOTE: Disks can only be attached to the servers in the same AZ. The AZ of a disk cannot be changed after the disk has been created.	-
Data Source (Optional)	Create from Backup Snapshot Image	Optional Create from Backup: The backup data is used to create the disk. Click Create from and choose Backup. On the displayed page, select the target backup and click OK. NOTE: One backup cannot be used for concurrent disk creation operations at the same time. For example, if you are creating disk A from a backup, this backup can be used to create another disk only after disk A has been created. If a disk is created from a backup of a system disk, the new disk can be used as a data disk only. Create from Snapshot: The snapshot data is used to create the disk. Click Create from and choose Snapshot. On the displayed page, select the target snapshot and click OK. NOTE: For details about how to create disks from snapshots, see Creating a Disk from a Snapshot. Create from Image: The image data is used to create the disk. Click Create from and choose Image. On the displayed page, select the target image and click OK. NOTE: The device type of the new disk is the same as that of the image's source disk. The encryption attribute of the new disk is the same as that of the image's source disk.	Create from Backup: autobackup-001
Disk Specifications	Disk Type	Mandatory EVS disk types vary depending on regions. See the EVS types displayed on the console. For more information about disk types, see Disk Types and Performance.	Ultra-high I/O
Disk Specifications	Capacity (GiB)	Mandatory The disk capacity. Only data disks can be created on the current page, and the disk size ranges from 10 GiB to 32,768 GiB. NOTE: When you use a backup to create a disk, the disk capacity must be greater than or equal to the backup size. In the condition that you do not specify a disk capacity, if the backup size is smaller than 10 GiB, the default capacity 10 GiB will be used as the disk capacity; if the backup size is greater than 10 GiB, the disk capacity will be consistent with the backup size. When you use a snapshot to create a disk, the disk capacity must be greater than or equal to the snapshot size. In the condition that you do not specify a disk capacity, if the snapshot size is smaller than 10 GiB, the default capacity 10 GiB will be used as the disk capacity; if the snapshot size is greater than 10 GiB, the snapshot size will be used as the disk capacity.	100 GiB
More	Advanced Settings Share SCSI Encryption	Optional Share If you select Share, a shared disk is created. A shared disk can be attached to up to 16 servers. If you do not select Share, a non-shared disk is created, and the disk can be attached to one a server only. If you select both SCSI and Share, a shared SCSI disk is created. NOTE: The sharing attribute of a disk cannot be changed after the disk is created. For details about shared EVS disks, see Managing Shared EVS Disks. SCSI If you select SCSI, a SCSI disk is created. Such disks allow the server OS to directly access the underlying storage media and send SCSI commands to the disks. If you do not select SCSI, a VBD disk is created. That said, the disk device type is VBD, the default device type. NOTE: The device type of a disk cannot be changed after the disk has been created. For details about the ECS types, OSs, and ECS software supported by SCSI EVS disks, see Device Types. Encryption This option is only used to encrypt data disks, and you need to create an agency to grant KMS access rights to EVS. After the access rights are granted, configure the KMS key name on the Encryption Settings page displayed: A key name is the identifier of the key, and you can use KMS Key Name to specify a KMS key and use it for encryption. You can select one of the following keys: Default Master Key: After the KMS access rights have been granted to EVS, the system automatically creates a Default Master Key evs/default. An existing or newly created CMK. For details, see "Key Management Service" > "Creating a Key" in the Data Encryption Workshop User Guide. NOTE: System disk encryption relies on the image. For details, see the Image Management Service User Guide. Before using the encryption function, you need to create an agency to grant KMS access rights to EVS. If you have the right to grant the permission, grant the KMS access rights to EVS directly. After the KMS access rights have been granted, follow-up operations do not require the rights to be granted again. If you do not have this permission, contact a user with the security administrator permissions to grant KMS access rights to EVS, then repeat the preceding operations. The encryption attribute of a disk cannot be changed after the disk has been created. For details, see Managing Encrypted EVS Disks.	-
More	Tag	Optional You can add tags when creating disks. Tags can help you identify, classify, and search for your disks. For details about tag rules, see Adding a Tag. NOTE: Except for tagging the disk during disk creation, you can also add, modify, or delete tags for existing disks. For more information about tags, see Managing EVS Tags.	-
Disk Name	-	Mandatory If you create a single disk, the name you entered will be used as the disk name. The name can contain a maximum of 64 characters. If you create multiple disks in a batch, the name you entered will be used as the prefix of disk names. An actual disk name will be composed of the name you entered and a four-digit number. The name can contain a maximum of 59 characters.	For example, if you create two disks and set volume for Disk Name, the EVS disk names will be volume-0001 and volume-0002.
Automatic Backup	-	CBR lets you back up EVS disks and ECSs and use the backups to restore data. After you configure automatic backup, the system will associate the EVS disk with the backup vault and apply the selected policy to the vault to periodically back up the disk. Do not use: Skip this configuration if backup is not required. If you need backup protection after a disk has been , log in to the CBR console, locate the desired vault, and associate the disk with the vault. Use existing: Vault: Select an existing vault from the drop-down list. Backup Policy: Select a backup policy from the drop-down list, or go to the CBR console and configure a desired one. Auto assign: Enter a vault name, which can contain a maximum of 64 characters, including letters, digits, underscores (_), and hyphens (-), for example, vault-f61e. The default naming rule is vault_xxxx. Enter the vault capacity, which is required for backing up the disk. The vault capacity cannot be less than the size of the disk to be backed up. The value ranges from the disk size to 10,485,760 in the unit of GiB. Select a backup policy from the drop-down list, or go to the CBR console and configure a desired one.	-
Enterprise Project	-	Mandatory When creating EVS disks, you can add the disks to an existing enterprise project. An enterprise project facilitates project-level management and grouping of cloud resources and users. The default project is default.	default
Quantity	-	Optional The preset disk quantity is 1, which means only one disk is created. You can create a maximum of 100 disks at a time. NOTE: If the disk is created from a backup, batch creation is not possible, and this parameter must be set to 1. If the disk is created from a snapshot, batch creation is not possible, and this parameter must be set to 1.	1

Click Next.
On the Details page, check the disk configuration.
- If you do not need to modify the configuration, click Submit.
- If you need to modify the configuration, click Previous.
In the disk list, view the disk status.

When the disk status changes to Available, the disk is successfully created.