Data Online Migration:Migrate data

Usage notes

When you migrate data by using Data Online Migration, take note of the following items:

• Data Online Migration accesses the source data address by using the public interfaces provided by the storage service provider of the source data address. The access behavior depends on the interface implementation of the storage service provider.

• When Data Online Migration is used for migration, it consumes resources at the source and the destination data addresses. This may interrupt your business. To ensure business continuity, we recommend that you enable throttling for your migration tasks or run the migration tasks during off-peak hours after careful assessment.

• Before a migration task starts, Data Online Migration checks the files at the source and the destination data addresses. If a file at the source data address and a file at the destination data address have the same name, and the File Overwrite Method parameter of the migration task is set to Yes, the file at the destination data address is overwritten during migration. If the two files contain different information and the file at the destination data address needs to be retained, we recommend that you change the name of one file or back up the file at the destination data address.

• The LastModified property of the source file is retained after the file is migrated to the destination bucket. If a lifecycle rule is configured for the destination bucket and takes effect, the migrated file whose last modification time is within the specified time period of the lifecycle rule may be deleted or archived in specific storage types.

Step 1: Create a source data address

1. Log on to the Data Online Migration console as the Resource Access Management (RAM) user that you created for data migration.

2. In the left-side navigation pane, choose Data Online Migration > Data Address. On the page that appears, click Create Data Address.

3. In the Create Data Address panel, configure the parameters and click OK. The following table describes the parameters.

   Parameter	Required	Description
   Data Type	Yes	The type of the source data address. Select Http/Https.
   Data Name	Yes	The name of the source data address. The name must be 3 to 63 characters in length. The name cannot contain special characters except for hyphens (-) and underscores (_).
   File Path	Yes	The path of the list file. Format: oss://{bucket}/{List file name}. For more information, see the Step 2: Upload a list file section of the "Preparations" topic.
   List Access Endpoint	Yes	The endpoint of the source data address. Specify an endpoint based on the region where the source bucket resides. For more information, see Regions and endpoints.
   List Access AK	Yes	The AccessKey pair of the RAM user that is used to read data from the source data address. The AccessKey pair is used by OSS to check whether the RAM user has the permissions to read data from the source data address.
   List Access SK	Yes

Step 2: Create a destination data address

1. In the left-side navigation pane, choose Data Online Migration > Data Address. On the page that appears, click Create Data Address.

2. In the Create Data Address panel, configure the parameters and click OK. The following table describes the parameters.

   Parameter	Required	Description
   Data Type	Yes	The type of the destination data address. Select OSS.
   Data Name	Yes	The name of the source data address. The name must be 3 to 63 characters in length. The name cannot contain special characters except for hyphens (-) and underscores (_).
   Data Region	Yes	The region in which the destination data address resides.
   Enable Transfer Acceleration	No	If you want to use Data Online Migration together with the transfer acceleration feature of Object Storage Service (OSS), enable the transfer acceleration feature for buckets. The transfer acceleration feature takes effect within 30 minutes after it is enabled. After you enable the feature, wait for 30 minutes before you create a migration job. Important If you use the transfer acceleration feature to access your OSS buckets, you are charged additional transfer acceleration fees. For more information, see Transfer acceleration.
   OSS Endpoint	Yes	The endpoint of the destination data address. Select an endpoint based on the region in which the destination data address resides. For more information, see Regions and endpoints.
   AccessKey Id	Yes	The AccessKey pair of the RAM user that is used to write data to the destination data address. The AccessKey pair is used by OSS to check whether the RAM user has the permissions to write data to the destination data address.
   AccessKey Secret	Yes
   OSS Bucket	Yes	The OSS bucket to which the data is migrated.
   OSS Prefix	No	The prefix of the destination data address. If you specify a prefix, the source data is migrated to the specified directory. The value cannot start with a forward slash (/) and must end with a forward slash (/). Example: data/to/oss/. If you do not specify a prefix, the source data is migrated to the root directory of the destination bucket.

Step 3: Create a migration job

1. In the left-side navigation pane, choose Data Online Migration > Migration Jobs. On the page that appears, click Create Job.

2. In the Create Job panel, read the terms of the migration service and select I agree to the above terms and activate the Data Transport service. Then, click Next.

3. In the Fee Reminder message, click Yes, Go Ahead.

4. In the Job Config step, configure the parameters and click Next. The following table describes the parameters.

   Parameter	Required	Description
   Job Name	Yes	The name of the source data address. The name must be 3 to 63 characters in length. The name cannot contain special characters except for hyphens (-) and underscores (_).
   Source Data Address	Yes	The source data address that you created.
   Destination Data Address	Yes	The destination data address that you created.
   Migration Type	Yes	Full: The system runs a full migration job. After all data is migrated, the migration job ends. If the data at the source data address changes after the migration is complete, you can submit another job to migrate all data. In this case, the system migrates only the data that changes. Important Before you start a full migration job, the system compares files at the source data address with those at the destination data address. If a file at the destination data address has the same name as a file at the source data address, the file at the destination data address is overwritten when one of the following conditions is met: The Content-Type property values of the source file and the destination file are different. The last modification time of the source file is later than that of the destination file. The size of the source file is different from the size of the destination file.
   File Overwrite Method	Yes	The method that is used to process the file at the source data address whose name is the same as that of a file at the destination data address. Valid values: LastModified: If a source file has the same name as a destination file, the system compares the last modified time indicated by the LastModified property of the files. If the last modification time of the file at the source data address is later than that of the file at the destination data address, the file at the source data address is migrated and the file at the destination data address is overwritten. If the last modification time of the file at the source data address is earlier than that of the file at the destination data address, the file at the source data address is not migrated and the file at the destination data address is retained. If the two files have the same last modification time, the system checks the values of the Size and Content-Type properties of the files. If the two files have the same Size and Content-Type values, the file at the source data address is not migrated. If the two files have different values of at least one property, the file at the source data address is migrated and the file at the destination data address is overwritten. Condition: If a source file has the same name as a destination file, the system compares the values of the LastModified, Size, and Content-Type properties of the files. If all property values of the two files are the same, the file at the source data address is not migrated. If the two files have different values of at least one property, the file at the source data address is migrated and the file at the destination data address is overwritten. All: If a source file has the same name as a destination file, the system performs no comparison and directly overwrites the destination file with the source file. No: If a source file has the same name as a destination file, the system performs no comparison and directly skips the source file in the migration. Warning If you select Condition or LastModified, earlier files may overwrite later files. If you select Condition or LastModified, make sure that the source files have LastModified, Size, and Content-Type values. Otherwise, the overwrite policy may become ineffective and data is not migrated as expected.

5. In the Data Prediction section of the Performance step, configure the Data Size and File Count parameters.

   Note

   To ensure a successful migration job, we recommend that you estimate the volume of data that you want to migrate as accurately as possible. For more information, see the Estimate the amount of data that you want to migrate section of the "Preparations" topic.

6. Optional. In the Flow Control section of the Performance step, configure the Time Range and Max Flow(MB/s) parameters and click Add.

   Note

   To ensure business continuity, we recommend that you configure the Time Range and Max Flow(MB/s) parameters based on the workload peaks and troughs.

7. Click Create and wait until the migration job is complete.

Step 4: Verify data