Creating a Synchronization Task

You can configure an event trigger in the source object storage service. This way, when an object is added or modified, the system automatically calls the OMS data synchronization API through FunctionGraph to synchronize the updated data to Huawei OBS.

Constraints

Fewer than 1,000,000 migration tasks have been created in your account in the past 24 hours.
There are fewer than 1,000,000 migration tasks in the Waiting state in your account.
You have fewer than 5 synchronization tasks in the Synchronizing state in your account.

Procedure

Table 1 introduces the complete process of creating a synchronization task for object storage migration.

**Table 1** Synchronization process
Step	Description
Preparations	Sign up for a Huawei Cloud account, complete real-name authentication, obtain the OMS permissions, and obtain AK/SK pairs for the source and destination accounts. Create a destination bucket for migration.
Step 1: Setting Source and Destination Parameters	Select the source and destination locations and set the parameters.
Step 2: Setting Task Parameters	Configure task parameters and create a synchronization task.
Step 3: Confirming and Tracking the Synchronization Task	Confirm the information specified for configuring the synchronization task. Start the synchronization task and check its resource status and migration stage.

Preparations

Before creating a synchronization task, prepare the account, permissions, and destination OBS bucket based on Table 2.

**Table 2** Preparations
Item	Requirement
Registering a Huawei Cloud account with required permissions	Sign up for a Huawei Cloud account and complete real-name authentication. If you have already signed up for a Huawei Cloud account and completed real-name authentication, skip this step. Visit Huawei Cloud and click Sign Up. Sign up for a Huawei Cloud account. (Optional) Complete real-name authentication. Real-name authentication is the process of submitting valid identity information (such as a passport or business license) for verification when you use cloud services offered in the Chinese mainland. There are individual real-name authentication and enterprise real-name authentication. According to relevant laws and regulations, unauthenticated accounts cannot purchase cloud services in the Chinese mainland and your account and rights may not be protected. For more information, see Real-Name Authentication Overview. To complete real-name authentication, refer to: Individual account: Individual Real-Name Authentication Enterprise account: Enterprise Real-Name Authentication Create an IAM user and grant permissions to the user. Skip this step if you use a Huawei Cloud account (administrator account). Create an IAM user. For details, see Creating an IAM User or Creating an IAM User (New Version). Grant permissions to the IAM user. Grant the system-defined policies OMS Administrator, OBS Administrator, KMS Administrator, and MgC MigrateAccess to the IAM user. For details about how to grant permissions, see Assigning Permissions to an IAM User or Assigning Permissions to an IAM User (New Version). Create custom policies to supplement the system-defined policies. For details about a custom policy and how to create a custom policy, see Source Permissions and Destination Permissions. Obtain AK/SK pairs and required permissions for the source and target accounts. For details about how to obtain an AK/SK pair for the source account, see Creating Access Keys for Access Cloud Platforms For details about how to obtain an AK/SK pair for the target account, see Creating an Access Key or Access Keys (New Version).
Creating a destination bucket	Create a destination bucket in advance to receive data from the source. For details, see Creating a Bucket.

Step 1: Setting Source and Destination Parameters

Log in to the OMS console.
In the navigation pane, choose Synchronization Tasks.
In the upper right corner, click Create Synchronization Task.
Read the service disclaimer, select I have read and agree to the service disclaimer, and click OK. The Create Synchronization Task page is displayed.

Set the source parameters based on Table 3.

**Table 3** Source parameters
Parameter	Description
Data Source	Select the source cloud service provider. Huawei Cloud AWS Alibaba Cloud Microsoft Azure Tencent Cloud Google Cloud Qiniu Cloud QingCloud Baidu Cloud Kingsoft Cloud UCloud
APP_ID	Enter the APPID, an identifier, of the account for logging in to the Tencent Cloud console. This parameter is only available if the source cloud service provider is Tencent Cloud.
Access Key ID	Enter the AK for accessing the source platform. It can contain a maximum of 100 characters.
Secret Access Key	Enter the SK for accessing the source platform. The SK matches the AK, and they form a pair. It can contain a maximum of 100 characters.
KMS Key	Disabled: The source key is not encrypted.
KMS Key	Enabled: The source key is encrypted. Before enabling this function, authorize OMS to access KMS. After that, a custom policy is granted, which contains: kms:cmk:get: Query key information. kms:dek:decrypt: Decrypt a data key. kms:dek:create: Create a DEK without plaintext. If you have the permission to grant access, grant KMS access permissions directly. After KMS access permissions are granted, follow-up operations do not require the permissions to be granted again. Then, you can perform the following operations: Select a custom key from the drop-down list. Alternatively, create one by referring to Creating a Custom Key. Currently, only the AES_256 and SM4 key algorithms are supported. NOTE: Enabling KMS encryption will incur fees. For details, see Pricing Details.
Specify Source Bucket	Enable this option if your source account does not have the permissions required to list buckets but has the permissions to list objects in buckets, obtain object metadata, and obtain object content. Then specify the bucket or path to be migrated. For details, see Table 4.

**Table 4** Description of **Specify Source Bucket**
Parameter	Description
Enable Specify Source Bucket	Select the region where the source bucket is located from the Region drop-down list. In the Bucket text box, enter the bucket or the path to be migrated. The path must include the bucket name. OMS will check whether the source platform can be connected using the information you provided. If the source platform can be connected, the system will notify you.
Disable Specify Source Bucket (This feature is disabled by default.)	Click the Bucket drop-down list or the refresh icon and select the bucket where data needs to be migrated. OMS will check whether the source platform can be connected using the information you provided. Once the source platform is connected, as long as your account has the necessary permissions to list buckets, all buckets in your account will appear in the Bucket drop-down list. NOTE: If the source account does not have the permissions required to list buckets, enable Specify Source Bucket.

Configure destination parameters based on Table 5.

**Table 5** Destination parameters
Parameter	Description
Access Key ID	Enter the AK for accessing Huawei Cloud. It can contain a maximum of 100 characters.
Secret Access Key	Enter the SK for accessing Huawei Cloud. The SK matches the AK, and they form a pair. It can contain a maximum of 100 characters.
KMS Key	Disabled: The destination key is not encrypted.
KMS Key	Enabled: The destination key is encrypted. Before enabling this function, authorize OMS to access KMS. After that, a custom policy is granted, which contains: kms:cmk:get: Query key information. kms:dek:decrypt: Decrypt a data key. kms:dek:create: Create a DEK without plaintext. If you have the permission to grant access, grant KMS access permissions directly. After KMS access permissions are granted, follow-up operations do not require the permissions to be granted again. Then, you can perform the following operations: Select a key from the KMS key drop-down list. Alternatively, create one by referring to Creating a Custom Key. Currently, only the AES_256 and SM4 key algorithms are supported. NOTE: Enabling KMS encryption will incur fees. For details, see Pricing Details.
Bucket	Select an OBS bucket for storing the migrated data.

Step 2: Setting Task Parameters

Click Next. The Set Task Parameters page is displayed.

Set the task parameters based on Table 6.

**Table 6** Task parameters
Parameter	Description
Task Name (Optional)	Enter a task name. If left empty, the name defaults to "<source-bucket-name>-<destination-bucket-name>_UUID". The name cannot be modified after the task is created.
Object Metadata	Determine whether to migrate metadata. If you select Do not migrate, OMS will only migrate the Content-Type and Content-Encoding metadata to ensure that the migration runs properly. If you select Migrate, OMS will migrate supported metadata. Only Chinese characters, English letters, digits, and hyphens (-) can be migrated. Other characters cannot be migrated. The following metadata types are supported: Content-Type, Content-Encoding, Content-Disposition, Content-Language, Cache-Control, Expires, WebsiteRedirectLocation, Storage-Class, and custom metadata.
Object Storage Class	Choose the storage class that your objects will be migrated to. If you select the default configuration, the storage class of the destination bucket will be used. For details about storage classes, see How Do I Choose Storage Classes?
Archive Data Restoration	Archived data must be restored before it can be migrated. You can enable this option if your source cloud service provider supports automatic restoration of archived data. This function is applicable to the following clouds: Huawei Cloud (COLD), Alibaba Cloud (Archive), Kingsoft Cloud (ARCHIVE), Tencent Cloud (ARCHIVE), and UCloud (ARCHIVE). If you do not enable this option, the system directly records archived objects in the list of objects that fail to be migrated, skips them, and continues to migrate other objects in the migration task. If you enable this option, the system automatically restores and migrates archived objects in the migration task. If an archived object fails to be restored, the system skips it and records it in the list of objects that failed to be migrated and continues to migrate other objects in the migration task. NOTE: It takes at least a minute to restore an archived object. The larger the archived object is, the longer it takes to restore it, but if an archived object cannot be restored within three minutes, the restoration fails. The time needed depends on the cloud service provider. For details, see the documentation of your source cloud service provider. Two types of fees are generated during archived data restoration: fees for API calls and fees for archived object restoration. These fees are billed by the source cloud service provider. After the restoration is complete, archived objects will be in the restored state for a certain period of time. During this period, objects can be downloaded or read. After this period expires, archived objects need to be restored again for migration. For details about how long they stay in the restored state, see the documentation of the cloud service provider. The copies generated for restoring archived objects will be stored for three days by default. If there are more than 3 TB of data or more than 3 million objects in a source bucket, create a migration task group to migrate data in case the migration fails because the restored data is archived again. Pausing or restarting a migration task will cause all archived data to be restored again, even if it was already restored. This operation will take additional time and generate extra costs. After objects are migrated from the source platform to Huawei Cloud, they are in the same storage class as the destination bucket.
Object Overwrite	Overwrite if source newer or different size: This is the default setting. If a source object has the same name as the paired destination object, the system compares the sizes and last modification time of the source and destination objects to determine whether to overwrite the destination object. The encryption status of the source and destination objects must be the same. If a source object was last modified more recently than or is not as large as its paired destination object, the source object will overwrite the destination object. Otherwise, the source object will be skipped. Never overwrite: The system always skips source objects and keeps their paired destination objects. Overwrite if different CRC64 checksum: This option is only available for migration within Huawei Cloud or from Alibaba Cloud or Tencent Cloud. If a source object has a CRC64 checksum different from the paired destination object, the source object will overwrite the destination object. Otherwise, the source object will be skipped. If one of them does not have a CRC64 checksum, their sizes and last modification times are checked. Always overwrite: The system always allows source objects to overwrite their paired destination objects.
Consistency Check	By size and last modification time: This is the default setting. The system checks object consistency with object size and last-modification time. If a source object and its paired destination object have the same size and the destination object's last-modification time is not earlier than the source object's, the system considers the object unnecessary to migrate or already successfully migrated. By CRC64 checksum: This option is only available for migration within Huawei Cloud or from Alibaba Cloud or Tencent Cloud. If a source object and its paired destination object have CRC64 checksums, the checksums are checked. Otherwise, their sizes and last modification times are checked.
Description	Enter a maximum of 255 characters.

Step 3: Confirming and Tracking the Synchronization Task

Click Next in the lower right corner of the page. The confirmation page is displayed.
Confirm the settings of the synchronization task and start the synchronization.
1. Check that the migration settings are correct.
  If the settings are incorrect, click Previous to return to the previous page for modification.
2. Click Synchronize Now. Read the prompted information carefully and click OK. The Request submitted page is displayed.
  The synchronization task is displayed in the synchronization task list.

In the task list, click the synchronization task name/ID. On the task details page, you can see the number of requested objects (this month), number of synchronized objects (this month), synchronized object size (this month), and synchronization task settings. Table 7 describes other related operations.

**Table 7** Other operations related to synchronization tasks
Operation	Description
Starting a synchronization task	You can only restart Paused synchronization tasks. For security purposes, the system does not save your personal data when you restart a synchronization task after it is stopped. You need to enter the AKs and SKs for accessing the source and destination buckets again to complete identity authentication.
Pausing a synchronization task	You can pause synchronization tasks only when they are in the Synchronizing state. Before pausing a synchronization task, you are advised to stop writing data to the source bucket and wait for 15 minutes. Otherwise, certain objects included in the received synchronization requests may fail to be synchronized.
Deleting a synchronization task	You can delete synchronization tasks only when they are in the Paused state.