All Products
Search
Document Center

Object Storage Service:Copy objects

Last Updated:Apr 11, 2024

You can copy objects to another directory in the same Object Storage Service (OSS) bucket or to another bucket that is located in the same region as the source bucket without changing the object content. In ossutil, you can use the cp command to copy objects.

Usage notes

  • To copy an object, you must have the oss:GetObject, oss:ListObjects, and oss:PutObject permissions. For more information, see Attach a custom policy to a RAM user.

  • This topic provides sample command lines that are based on the 64-bit Linux system. For other systems, replace ./ossutil64 in the commands with the corresponding binary name. For more information, see ossutil command reference.

  • You cannot run the cp command to copy objects to a bucket that belongs to another Alibaba Cloud account or to a bucket that is located in a different region. If you want to copy objects to a bucket that belongs to another Alibaba Cloud account or to a bucket that is located in a different region, use ossimport or Data Online Migration.

  • You can use the cp command to copy objects, but not parts.

  • Appendable objects cannot be copied.

  • You must have read permissions on the source object and read and write permissions on the destination bucket. Otherwise, the copy operation fails. For more information about how to copy an object, see Copy objects.

Command syntax

./ossutil64 cp cloud_url cloud_url
[-r, --recursive]
[-f --force]
[-u --update]
[--disable-ignore-error]
[--only-current-dir]
[--bigfile-threshold <value>]
[--part-size <value>]
[--checkpoint-dir <value>]
[--encoding-type <value>]
[--include <value>]
[--exclude <value>]
[--meta <value>]
[--acl <value>]
[--disable-crc64]
[--payer <value>]
[-j, --job <value>]
[--parallel <value>]
[--version-id <value>]
[--start-time <value>]
[--end-time <value>]

The following table describes the parameters and options in the command syntax.

Parameter/Option

Description

cloud_url

The paths of the source and destination objects. The path follows the oss://bucketname/objectname format. For example, to copy a source object named srcobject.jpg from the examplebucket bucket to a destination object named destobject.jpg in the same bucket, set the path of the source object to oss://examplebucket/srcobject.jpg and the path of the destination object to oss://examplebucket/destobject.jpg.

-r, --recursive

Specifies recursion. If you specify this option, ossutil performs the operation on all objects in the bucket that meet the specified conditions. If you do not specify this option, ossutil performs the operation only on the specified object.

-f --force

Forces the operation without requiring confirmation.

-u, --update

Specifies that ossutil copies the source object only when the object does not exist in the destination bucket or when the last modified time of the source object is later than that of the destination object.

--disable-ignore-error

Specifies that errors are not ignored for batch operations.

--only-current-dir

Specifies that only objects in the current directory are copied. Subdirectories and objects in these subdirectories are not copied.

-bigfile-threshold

The object size threshold for using resumable upload for the operation. Unit: bytes.

The default object size threshold is 100 MB.

Valid values: 0 to 9223372036854775807.

--part-size

The part size. Unit: bytes. By default, ossutil determines the part size based on the object size.

Valid values: 1 to 9223372036854775807.

--checkpoint-dir

The directory in which the checkpoint information of the resumable upload task is stored. If the task fails, ossutil automatically creates a directory named .ossutil_checkpoint and saves the checkpoint file in the directory. After the task is complete, ossutil deletes the directory. If you specify this option, make sure that the directory can be deleted.

--encoding-type

The method used to encode the names of objects. If you specify this option, set the value to url. If you do not specify this option, the names of objects are not encoded.

--include

Includes all objects that meet the specified conditions.

--exclude

Excludes all objects that meet the specified conditions.

--meta

The object metadata. Specify object metadata in the header:value#header:value format. Example: Cache-Control:no-cache#Content-Encoding:gzip. For more information, see set-meta.

--acl

The access control list (ACL) of the objects. Valid values:

  • default: The ACL of the objects is the same as that of the bucket in which the objects are stored. This is the default ACL setting for objects.

  • private: Only the bucket owner can perform read and write operations on the objects in the bucket. Other users cannot access the objects in the bucket.

  • public-read: Only the bucket owner can perform write operations on the objects in the bucket. Other users, including anonymous users, can perform only read operations on the objects in the bucket. This may result in unauthorized access to data in your bucket and high fees. If a user uploads prohibited data or information, your legitimate interests and rights may be infringed. We recommend that you do not set the ACL to this value except in special cases.

  • public-read-write: All users, including anonymous users, can perform read and write operations on the objects in the bucket. This may result in unauthorized access to data in your bucket and high fees. Proceed with caution when you set the ACL to public-read-write.

--disable-crc64

Disables 64-bit cyclic redundancy check (CRC-64). By default, ossutil enables CRC-64 during data transmission.

--payer

The payer of the traffic and request fees. If you want the requester who accesses the resources in the specified path to pay the traffic and request fees, set this option to requester.

-j, --jobs

The number of concurrent tasks that can be performed across multiple objects. Valid values: 1 to 10000. Default value: 3.

--parallel

The number of concurrent tasks that can be performed on a single object. Valid values: 1 to 10000. If you do not configure this option, ossutil specifies a value based on the operation type and the object size.

--version-id

The version ID of the object that you want to copy. You can specify this option for objects only in a bucket for which versioning is enabled.

--start-time

The beginning of the time range to filter objects by. The value is a UNIX timestamp. Objects whose last modified time is earlier than the UNIX timestamp are ignored.

Note

Only ossutil V1.7.18 and later support this parameter. For more information about how to update ossutil, see update.

--end-time

The end of the time range to filter objects by. The value is a UNIX timestamp. Objects whose last modified time is later than the timestamp are ignored.

Note
  • If both --start-time and --end-time are specified, the command applies only to objects whose last modified time is within the range specified by --start-time and --end-time.

  • Only ossutil V1.7.18 and later support this parameter. For more information about how to update ossutil, see update.

You can use the -j, --jobs and --parallel options to adjust performance if the default concurrency value does not meet your performance requirements. By default, ossutil calculates the value of --parallel based on the object size. When you copy multiple large objects, the actual number of concurrent tasks is calculated by multiplying the value of -j, --jobs by the value of --parallel.

  • We recommend that you adjust the number of concurrent tasks to a value smaller than 100 if the resources, such as network bandwidth, memory, and CPU of your Elastic Compute Service (ECS) instance or server, are limited. If resources, such as network bandwidth, memory, and CPU, are left idle, you can increase the number of concurrent tasks.

  • If the number of concurrent tasks is too large, the copy operation performance of ossutil may decrease because threads switch and compete for resources. In addition, an end-of-file (EOF) error may occur. To prevent these issues, you can adjust the values of -j, --jobs and --parallel based on your available resources. To perform stress testing, we recommend that you initially specify small values for the options and gradually increase the values to find the optimal values.

Sample environment

The examples in this topic show how to copy objects between different directories in the same bucket and between buckets in Linux. To use the sample commands in your actual business scenario, you need to modify option and parameter settings based on your operating system and environment. Sample environment:

  • Operating system: Linux

  • Source bucket: examplebucket1

  • Directory 1 in the source bucket: srcfolder1

  • Directory 2 in the source bucket: srcfolder2

  • Destination bucket: examplebucket2

  • Directory in the destination bucket: desfolder

Specify whether to copy the source directory

If the source path does not end with a forward slash (/), all objects whose names contain the specified prefix in the source bucket are copied to the destination bucket. If the source path ends with a forward slash (/), only the objects in the specified directory are copied to the destination bucket.

For example, the following objects are stored in the srcfolder1 directory in the source bucket named examplebucket1:

srcfolder1/exampleobject1.txt
srcfolder1/exampleobject2.png
srcfolder1/dir1/
srcfolder1/dir1/exampleobject3.jpg
srcfolder1/dir2/
srcfolder1/dir2/exampleobject4.jpg
  • Copy objects from a path that does not end with a forward slash (/)

    ./ossutil64 cp oss://examplebucket1/srcfolder1  oss://examplebucket2 -r

    The following objects are copied from the source bucket to the destination bucket named examplebucket2:

    srcfolder1/exampleobject1.txt
    srcfolder1/exampleobject2.png
    srcfolder1/dir1/
    srcfolder1/dir1/exampleobject3.jpg
    srcfolder1/dir2/
    srcfolder1/dir2/exampleobject4.jpg
  • Copy objects from a path that ends with a forward slash (/)

    ./ossutil64 cp oss://examplebucket1/srcfolder1/  oss://examplebucket2 -r

    The following objects are copied from the source bucket to the destination bucket named examplebucket2:

    exampleobject1.txt
    exampleobject2.png
    dir1/
    dir1/exampleobject3.jpg
    dir2/
    dir2/exampleobject4.jpg

Perform a simple copy

  • Copy a single object

    ./ossutil64 cp oss://examplebucket1/examplefile.txt oss://examplebucket1/srcfolder2/                                 
  • Copy incremental objects

    If you specify the --update option when you copy multiple objects, ossutil copies the objects only when the destination objects do not exist, or the last modified time of the source objects is later than that of the destination objects. You can run the following command to copy incremental objects:

    ./ossutil64 cp oss://examplebucket1/srcfolder1/ oss://examplebucket2/path2/ -r --update

    You can use this option to skip copied objects and copy only objects that fail to be copied.

  • Copy multiple objects at a time

    Run the following command to copy objects in the srcfolder1 directory whose last modified time is within the range of 10:09:18 (UCT+8) October 31, 2023 to 12:55:58 (UTC+8) October 31, 2023:

    ./ossutil64 cp -r oss://examplebucket1/srcfolder1/ oss://examplebucket2/path2/ --start-time 1698718158 --end-time 1698728158
  • Rename an object

    ./ossutil64 cp oss://examplebucket1/examplefile.txt oss://examplebucket1/example.txt                        

    When you run the cp command to rename an object, the original object still exists. You can delete the original object after you rename the object.

  • Copy only objects in the current directory and ignore subdirectories

    ./ossutil64 cp oss://examplebucket1/srcfolder1/ oss://examplebucket1/srcfolder2/ --only-current-dir -r
  • Change the metadata of an object

    When you copy an object, you can use the --meta option to change the metadata of the object. The value of this option is in the header:value#header:value... format.

    ./ossutil64 cp oss://examplebucket1/examplefile.txt oss://examplebucket1/ --meta=Cache-Control:no-cache
  • Copy an object from a bucket for which pay-by-requester is enabled to a bucket for which pay-by-requester is disabled

    ./ossutil64 cp oss://examplebucket1/examplefile.txt oss://examplebucket2/desfolder/  --payer=requester

Copy multiple objects that meet specific conditions

To copy objects that meet specific conditions, you can specify --include and --exclude.

  • Copy all objects that are not in the JPG format

    ./ossutil64 cp oss://examplebucket1/srcfolder1/ oss://examplebucket2/desfolder/ --exclude "*.jpg" -r
  • Copy all objects that contain abc in their names and are not in the JPG or TXT format

    ./ossutil64 cp oss://examplebucket1/srcfolder1/ oss://examplebucket2/desfolder/ --include "*abc*" --exclude "*.jpg" --exclude "*.txt" -r

Change the storage class of an object

When you overwrite an object, you can specify the --meta option to change the storage class of the object. Valid values:

  • Standard: the Standard storage class

  • IA: the Infrequent Access storage class

  • Archive: the Archive storage class

  • ColdArchive: the Cold Archive storage class

  • DeepColdArchive: the Deep Cold Archive storage class

For more information about storage classes, see Overview.

Important

If you use the -- meta option to change the storage class of an object, the existing user metadata of the object is overwritten by default. If you want to change the storage class and retain the existing user metadata of the object, you must include the x-oss-metadata-directive:COPY option.

Overwrite the existing user metadata of an object

  • Change the storage class of an object to Archive

    ./ossutil64 cp oss://examplebucket1/srcfolder1/examplefile.txt oss://examplebucket1/srcfolder1/examplefile.txt --meta X-oss-Storage-Class:Archive
  • Change the storage class of all objects in a specific directory to Standard

    ./ossutil64 cp oss://examplebucket1/srcfolder1/ oss://examplebucket1/srcfolder1/ --meta X-oss-Storage-Class:Standard -r

Retain the existing user metadata of an object

  • Run the following command to change the storage class of a specific object to IA and retain the existing user metadata of the object:

    ./ossutil64 cp oss://examplebucket1/srcfolder1/examplefile.txt oss://examplebucket1/srcfolder1/examplefile.txt --meta X-oss-Storage-Class:IA#x-oss-metadata-directive:COPY
  • Run the following command to change the storage class of all objects in a specific directory to Standard and retain the existing user metadata of the objects:

    ./ossutil64 cp oss://examplebucket1/srcfolder1/ oss://examplebucket1/srcfolder1/ --meta X-oss-Storage-Class:Standard#x-oss-metadata-directive:COPY -r -f
Important
  • Before you can change the storage class of Archive, Cold Archive, or Deep Cold Archive objects to Standard or IA by running the cp command, run the restore command to restore the objects. If you enable real-time access of Archive objects, you can change the storage class of Archive objects without the need to restore them. For more information, see Real-time access of Archive objects.

  • If you change the storage class of an object to IA, Archive, Cold Archive, or Deep Cold Archive and the object is stored for less than the minimum storage duration, you are charged based on the entire minimum storage duration. For more information, see Storage fees.

  • When you run the cp command to change the storage class of an object that is larger than 100 MB, ossutil calculates an appropriate part size based on the object size by default. If the part size cannot meet your requirements, you can use --part-size to change the part size. Make sure that the number of parts is smaller than 10,000.

Modify the tags of an object

You can add --tagging to the cp command to modify the tags of an object. Separate the tags with ampersands (&). You can run the following command to modify the tags of an object:

./ossutil64 cp oss://examplebucket1/examplefile.txt oss://examplebucket1/ --tagging "abc=1&bcd=2&……"

For more information about object tagging, see object-tagging.

Copy and encrypt an object

When you copy an object, you can specify the server-side encryption method to encrypt the object. For more information, see Server-side encryption.

  • Copy an object and specify AES-256 encryption for the destination object

    ./ossutil64 cp oss://examplebucket1/examplefile.txt oss://examplebucket1/srcfolder2/ --meta=x-oss-server-side-encryption:AES256
  • Copy an object and specify SSE-KMS encryption for the destination object

    ./ossutil64 cp oss://examplebucket1/examplefile.txt oss://examplebucket2/desfolder/ --meta=x-oss-server-side-encryption:KMS
    Important

    When you use Key Management Service (KMS) to encrypt an object, OSS creates a customer master key (CMK) in KMS for the object. You are charged a small amount of fees when the KMS API operation is called. For more information, see Billing of KMS.

  • Copy an object and specify SSE-KMS encryption with a specific CMK for the destination object

    ./ossutil64 cp oss://examplebucket1/examplefile.txt oss://examplebucket2/desfolder/ --meta=x-oss-server-side-encryption:KMS#x-oss-server-side-encryption-key-id:7bd6e2fe-cd0e-483e-acb0-f4b9e1******

Restore objects in a versioning-enabled bucket

After you enable versioning for a bucket, objects that are overwritten or deleted in the bucket are saved as previous versions. You can add --version-id to the cp command to make a previous version of an object the latest version. Sample command:

./ossutil64 cp oss://examplebucket1/examplefile.txt oss://examplebucket2/ --version-id  CAEQARiBgID8rumR2hYiIGUyOTAyZGY2MzU5MjQ5ZjlhYzQzZjNlYTAyZDE3MDRk
Important
  • To use the --version-id option, you need to run the ls --all-versions command to obtain the version IDs of the object.

  • The --version-id option can be used only for objects in versioning-enabled buckets. For more information about how to enable versioning for a bucket, see bucket-versioning.

Common options

If you use ossutil to switch to a bucket that is located in another region, add the -e option to the command to specify the endpoint of the region in which the specified bucket is located. If you use ossutil to switch to a bucket that belongs to another Alibaba Cloud account, add the -i option to the command to specify the AccessKey ID of the specified account, and add the -k option to the command to specify the AccessKey secret of the specified account.

For example, you can run the following command to copy the srcobject.png object in the root directory of the source bucket named examplebucket to the destination bucket named destbucket. The destination bucket is located in the China (Shanghai) region and is owned by another Alibaba Cloud account.

./ossutil64 cp oss://examplebucket/srcobject.png  oss://destbucket  -e oss-cn-shanghai.aliyuncs.com -i LTAI4Fw2NbDUCV8zYUzA****  -k 67DLVBkH7EamOjy2W5RVAHUY9H****

For more information about common options, see Common options.