Tenant Cloud Storage Cloud Object Storage Developer Guide Multipart Copy

Multipart Copy

Last Updated At: 2025-10-21 09:10:00

Applicable Scenario

When you need to replicate an object that is larger than 5 GB, you need to use multipart replication. Use the multipart upload API to create an object and use the Part Copy feature to carry the x-cos-copy-source header to specify the source object that you want to replicate. The process includes the following steps:

  1. Initialize an object for multipart upload.
  2. Replicate the data of the source object; specify the x-cos-copy-range header. You can only replicate up to 5 GB at a time.
  3. Complete the multipart upload.

You can use the SDKs provided by the cloud platform's Cloud Object Storage (COS) to easily complete a multipart replication operation.

Usage Instructions

Using Java SDKs

COS supports AWS Java SDK. See Using AWS S3 SDK to Access COS to access COS, and operate according to the File Copying section in the official documentation of AWS Java SDK 2.20.0.