Simple Log Service allows you to replicate data from a source Logstore to a destination Logstore. To replicate the data, you can create a data transformation rule for the source Logstore. This topic describes how to replicate data from a source Logstore to a destination Logstore in a typical scenario.
Scenario
In this example, the access logs of a company are collected and stored in multiple projects of an Alibaba Cloud account. The company wants to replicate the access logs from the logstore-a Logstore of the project-a project to the logstore-b Logstore of the project-b project. Then, the company can query and analyze the data in the project-b project in a centralized manner. To replicate data from the logstore-a Logstore to the logstore-b Logstore, the company can use the replication feature in Simple Log Service. 
To use the replication feature, you must make sure that the following requirements are met:
A Logstore named logstore-a is created and data is written to the Logstore.
The performance of the logstore-b Logstore is evaluated, for example, the number of shards. For more information, see Performance guide.
A Logstore named logstore-b is created. For more information, see Manage a Logstore.
Procedure
Log on to the Simple Log Service console.
In the Projects section, click the project-a project.
On the tab, click the logstore-a Logstore.
On the Search & Analysis page, click Data Transformation in the upper-right corner to enable the data transformation mode.
On the page that appears, click Save as Transformation Rule.
In the Create Data Transformation Rule panel, set the required parameters. The following table describes the parameters.
Parameter
Description
Rule Name
The name of the transformation rule. Enter test.
Authorization Method
Authorizes Simple Log Service to read data from the logstore-a Logstore. The default role is used as an example. Select Default Role.
Target Name
The name of the storage target. Enter test.
Target Region
The region where the destination project resides. Select China (Hangzhou).
Target Project
The name of the destination project. Enter project-b.
Target Logstore
The name of the destination Logstore. Enter logstore-b.
Authorization Method
Authorizes Simple Log Service to read data from and write data to the logstore-b Logstore.
The default role is used as an example. Select Default Role.
Time Range
The time when the logs are received. The All value indicates that the data in the source Logstore is transformed from the first log entry until the transformation task is manually stopped. Select All.
For information about other parameters, see Create a data transformation job.
Click OK.
Result
In the Projects section, click the project-b project. On the tab, select the logstore-b Logstore. You can view the data that is replicated from the logstore-a Logstore. 