Purchasing an EVS Disk
When a server is created, the system disk is automatically added. You do not need to explicitly purchase the system disk.
You can purchase data disks during or after the server creation. If you purchase data disks during the server creation, the system will automatically attach the data disks to the server. If you purchase data disks after the server creation, you need to manually attach the purchased data disks to the server.
- Visit the Huawei 3data Cloud website and log in to the management console.
- Under Storage, click Elastic Volume Service.
The Elastic Volume Service page is displayed.
- Click Buy Disk.
- Configure the basic information about the EVS disk, as shown in Table 1.
Table 1 Parameter description
You can pay for EVS disks in two ways:
Region and AZ
Specifies the region of the tenant. Select the current region from the drop-down list in the upper left corner of the page.
Specifies the availability zone (AZ) where the EVS disk is to be created.NOTE:
EVS disks can only be attached to the servers in the same AZ.
Disk Creation Settings
You can create new EVS disks or create EVS disks using the data source.
- If Do not specify is selected, the EVS disks you created are brand new, and no data is available.
- If Create from backup is selected, the backup data is used to create EVS disks.
When Create from backup is selected, parameter Source Backup is mandatory.
Click Select. On the displayed page, select the target backup and click OK.
- If Create from snapshot is selected, the snapshot data is used to create EVS disks.
When Create from snapshot is selected, parameter Source Snapshot is mandatory.
Click Select. On the displayed page, select the target snapshot and click OK.NOTE:
For details about the EVS disk creation from snapshots, see section Creating an EVS Disk Using a Snapshot.
Do not specify
- Common I/O
- Ultra-high I/O
Specifies the disk size.The parameter value is as follows:
- System disk: 1 GB to 1024 GB
- Data disk: 10 GB to 32768 GB
- When you use a backup to create an EVS disk, the disk capacity must be greater than or equal to the backup size. In the condition that you do not specify the disk capacity, if the backup size is smaller than 10 GB, the default capacity 10 GB will be used as the disk capacity; if the backup size is greater than 10 GB, the disk capacity will be consistent with the backup size.
- When you use a snapshot to create an EVS disk, the disk capacity must be greater than or equal to the snapshot size. In the condition that you do not specify the disk capacity, if the snapshot size is smaller than 10 GB, the default capacity 10 GB will be used as the disk capacity; if the snapshot size is greater than 10 GB, the disk capacity will be consistent with the backup size.
- The system shows you the maximum number of EVS disks as well as the maximum disk capacity allowed to purchase. To ensure effective resource usage, if the disk capacity you need exceeds the upper limit, click Apply for Higher Quota to obtain a higher quota. You can purchase the disk capacity you need after the request is approved.
Disk encryption is used for data disk encryption only. For system disk encryption, see the Image Management Service User Guide.
If Enable is selected, an encrypted EVS disk is created, and the following parameters will be displayed:
- Create Xrole
A Xrole is a trust relationship between two tenants or services. A tenant can create a Xrole to grant resource access rights to another tenant or service. If the KMS access rights are not granted to EVS, this button will be displayed. Otherwise, this button will not be displayed.
Click Create Xrole to grant the KMS access rights to EVS. The system automatically creates a Xrole and names it EVSAccessKMS. When EVSAccessKMS is displayed for Xrole Name, the KMS access rights have been granted to EVS, and EVS can obtain KMS keys for encrypting or decrypting EVS disks.
After the KMS access rights have been granted, follow-up operations do not require the rights to be granted again.
- KMS Key Name
KMS Key Name is displayed only after the EVSAccessKMS Xrole has been created. For details, see "Create Xrole" above.KMS Key Name is the identifier of the key, and you can use KMS Key Name to specify the KMS key that is to be used for encryption. One of the following keys can be used:
- Default Master Key: After the KMS access rights have been granted to EVS, the system automatically creates a Default Master Key and names it evs/default.
- CMKs: Existing or newly created CMKs. For details, see in the Key Management Service User Guide.
Before you use the EVS disk encryption function, the KMS access rights have to be granted to EVS. If you have the rights granting permission, grant the KMS access rights to EVS directly. If you do not have this permission, contact a user with the security administrator rights to grant the KMS access rights to EVS, then repeat the preceding operations. For details, see section EVS Disk Encryption.
- If VBD is selected, VBD device type disks are created. VBD is the default device type of EVS disks.
- If SCSI is selected, SCSI device type disks are created. Such EVS disks allow the server OS to directly access the underlying storage media and send SCSI commands to the disks.
- When a disk is created from a snapshot, the device type of the newly created disk will be consistent with that of the snapshot's source disk.
- For details about the ECS types, OSs, and ECS software supported by SCSI device type EVS disks, see section Device Types and Usage Instructions.
- If Disable is selected, a common EVS disk is created.
- If Enable is selected, a shared EVS disk is created, and the shared disk can be attached to multiple servers.
When both SCSI and Enable are selected, a shared EVS disk with device type SCSI is created.NOTE:
For details about shared EVS disks, see section Managing a Shared EVS Disk.
Auto backup is a function provided by VBS. If auto backup is enabled, the system automatically creates backups for the EVS disk data at specified time points and deletes outdated backups according to the configured backup policy.
When Enable is selected, a backup policy must be configured. You can either use the default backup policy or customize the policy based on your service requirements.NOTE:
For details about the backup policy, see section Managing EVS Backup.
- If you create disks one by one, this parameter value is used as the actual disk name. The value can contain a maximum of 255 bytes.
- If you create disks in a batch, this parameter value is used as the prefix of disk names, and one disk name will be composed of the parameter value and a four-digit number. The value can contain a maximum of 250 bytes.
For example, if you create two disks and set volume for Disk Name, the EVS disk names will be volume-0001 and volume-0002.
Mandatory if you have selected Yearly/Monthly for Billing Mode
The validity period ranges from 1 month to 3 years.
Specifies the number of disks to be created. The default value is set to 1, which means only one disk is created. Currently, you can create up to 100 disks at a time.NOTE:
- If the EVS disk is created from a backup, batch creation is not supported, and this parameter must be set to 1.
- If the EVS disk is created from a snapshot, batch creation is not supported, and this parameter must be set to 1.
- The system shows you the maximum number of EVS disks as well as the maximum disk capacity allowed to purchase. To ensure effective resource usage, if the number of EVS disks you need exceeds the upper limit, click Apply for Higher Quota to obtain a higher quota. You can purchase the disks you need after the request is approved.
- Click Buy Now if you have selected Yearly/Monthly for Billing Mode.
Click Apply Now if you have selected Metered for Billing Mode.
- On the Confirm Specifications page, you can confirm the disk details.
- After confirming the information, read and agree to the service agreement, and click Submit to create an EVS disk.
- If you need to modify the specifications, click Previous to modify parameters.
- Pay for EVS disks as prompted and click OK.
The Elastic Volume Service page is displayed.
- In the EVS disk list, view the disk status.
If the disk status changes to Available, the disk is successfully created.