Block Services

Creating a StorageClass

Prepare a StorageClass configuration file, for example, msc .yaml. For details about the StorageClass configuration, see the following example.
Run the following command to create a StorageClass using the configuration file.
```
kubectl apply -f mysc.yaml
```

Run the following command to view the information about the created StorageClass.

kubectl get sc mysc

The following is an example of the command output.

NAME   PROVISIONER      RECLAIMPOLICY   VOLUMEBINDINGMODE   ALLOWVOLUMEEXPANSION   AGE
mysc   csi.huawei.com   Delete          Immediate           true                   8s

Block StorageClass Configuration Example

If LUNs are used as storage resources and the file system needs to be formatted to a local file system, refer to the following example.

kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: mysc
provisioner: csi.huawei.com
parameters:
  backend: lun-181
  pool: StoragePool001
  volumeType: lun
  allocType: thin
  fsType: ext4

StorageClass Parameters Supported by Block Services

Table 1 StorageClass configuration parameters

Parameter	Description	Mandatory	Default Value	Whether the Volume Management Takes Effect	Remarks
metadata.name	User-defined name of a StorageClass object.	Yes	-	Yes	Take Kubernetes v1.22.1 as an example. The value can contain digits, lowercase letters, hyphens (-), and periods (.), and must start and end with a letter or digit.
provisioner	Name of the provisioner.	Yes	csi.huawei.com	Yes	Set this parameter to the driver name set during Huawei CSI installation. The value is the same as that of driverName in the values.yaml file.
reclaimPolicy	Reclamation policy. The following types are supported: Delete: Resources are automatically reclaimed. Retain: Resources are manually reclaimed.	No	Delete	Yes	Delete: When a PV/PVC is deleted, resources on the storage device are also deleted. Retain: When a PV/PVC is deleted, resources on the storage device are not deleted.
allowVolumeExpansion	Whether to allow volume expansion. If this parameter is set to true, the capacity of the PV that uses the StorageClass can be expanded.	No	false	Yes	This function can only be used to expand PV capacity but cannot be used to reduce PV capacity.
mountOptions	List of mount parameters, which can be used to specify the parameters of the -o option when the mount command is executed on a host.	No	-	Yes	For details about common parameters in mountOptions, see Table 2. You can also specify other mount parameters.
parameters.backend	Name of the backend where the resource to be created is located. This field must be set if parameters.pool is set.	Conditionally mandatory	-	No	If this parameter is not set, Huawei CSI will randomly select a backend that meets the capacity requirements to create resources. You are advised to specify a backend to ensure that the created resource is located on the expected backend.
parameters.pool	Name of the storage resource pool where the resource to be created is located.	No	-	No	If this parameter is not set, Huawei CSI will randomly select a storage pool that meets the capacity requirements from the selected backend to create resources. You are advised to specify a storage pool to ensure that the created resource is located in the expected storage pool.
parameters.volumeType	Type of the volume to be created. The following types are supported: lun: A LUN is provisioned on the storage side. fs: A file system is provisioned on the storage side. dtree: A volume of the Dtree type is provisioned on the storage side.	Yes	-	Yes	The value is fixed to lun.
parameters.allocType	Allocation type of the volume to be created. The following types are supported: thin: Not all required space is allocated during creation. Instead, the space is dynamically allocated based on the usage. thick: All required space is allocated during creation.	No	thin	No	If this parameter is set to thin, the required space is not allocated immediately when a volume is created. Instead, the space is dynamically allocated based on the usage.
parameters.fsType	Type of a host file system. The supported types are: ext2 ext3 ext4 xfs	No	ext4	No	This parameter is available only when volumeMode of the PVC is set to Filesystem.
parameters.qos	LUN/NAS QoS settings of the PV on the storage side. The value of the parameter is JSON character strings in dictionary format. A character string is enclosed by single quotation marks and the dictionary key by double quotation marks. Example: '{"maxMBPS": 999, "maxIOPS": 999}'	No	-	No	For details about the supported QoS configurations, see Table 3.
parameters.fsPermission	Permission on the directory mounted to a container.	No	-	No	For details about the configuration format, refer to the Linux permission settings, for example, 777 and 755.
parameters.disableVerifyCapacity	Whether to disable volume capacity verification. After this function is disabled, the system will not verify whether the volume capacity is an integer multiple of the sector size. The value can be: "true": disables volume capacity verification. "false": enables volume capacity verification. NOTICE: When Red Hat OpenShift Virtualization is used to connect to CSI, this parameter must be set to true.	No	"true"	Yes	For OceanStor Pacific SAN, the sector size is 1 MiB.

Table 2 Common parameters in mountOptions

Parameter	Description	Mandatory	Default Value	Remarks
mountOptions.discard	Automatically triggers the Trim or Discard operation when a file system is mounted. This operation instructs a block device to release unused blocks.	No	-	The xfs and ext4 file systems are supported.

Table 3 Supported QoS configurations

Parameter	Description	Remarks
maxMBPS	Maximum bandwidth. This is a restriction policy parameter.	This parameter is mandatory. The value is an integer greater than 0, expressed in MB/s. For details about the maximum value, see the actual limit of the storage device. For example, the maximum value of OceanStor Pacific NAS is 1073741824.
maxIOPS	Maximum IOPS. This is a restriction policy parameter.	This parameter is mandatory. The value is an integer greater than 0. For details about the maximum value, see the actual limit of the storage device. For example, the maximum value of OceanStor Pacific NAS is 1073741824000.