Monitoring your data transfers with task reports
Task reports provide detailed information about what AWS DataSync attempts to transfer, skip, verify, and delete during a task execution. For more information, see How DataSync transfers files, objects, and directories.
Task reports are generated in JSON format. You can customize the level of detail in your reports:
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Summary only task reports give you the necessary details about your task execution, such as how many files transferred and whether DataSync could verify the data integrity of those files.
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Standard task reports include a summary plus detailed reports that list each file, object, or folder that DataSync attempts to transfer, skip, verify, and delete. With a standard task report, you can also specify the report level to show only the task execution's errors or its successes and errors.
Use cases
Here are some situations where task reports can help you monitor and audit your data transfers:
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When migrating millions of files, quickly identify files that DataSync has issues transferring.
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Verify chain-of-custody processes for your files.
Summary only task reports
A report that's only a summary of a task execution includes the following details:
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The AWS account that ran the task execution
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The source and destination locations
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The total number of files, objects, and folders that were skipped, transferred, verified, and deleted
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The total bytes (logical and physical) that were transferred
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If the task execution was completed, canceled, or encountered an error
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The start and end times (including the total time of the transfer)
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The task's settings (such as bandwidth limits, data integrity verification, and other options for your DataSync transfer)
Standard task reports
A standard task report includes a summary of your task execution plus detailed reports of what DataSync attempts to transfer, skip, verify, and delete.
Report level
With standard task reports, you can choose one of the following report levels:
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Errors only
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Successes and errors (essentially a list of everything that happened during your task execution)
For example, you might want to see which files DataSync skipped successfully during your transfer and which ones it didn't. Files that DataSync skipped successfully might be ones that you purposely want DataSync to exclude because they already exist in your destination location. However, a skipped error for instance might indicate that DataSync doesn't have the right permissions to read a file.
Transferred reports
A list of files, objects, and directories that DataSync attempted to transfer during your task execution. A transferred report includes the following details:
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The paths for the transferred data
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What was transferred (content, metadata, or both)
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The metadata, which includes the data type, content size (objects and files only), and more
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The time when an item was transferred
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The object version (if the destination is an Amazon S3 bucket that has versioning enabled)
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If something was overwritten in the destination
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Whether an item transferred successfully
Note
When moving data between S3 buckets, the prefix that you specify in your source location can show up in your report (or in Amazon CloudWatch logs), even if that prefix doesn't exist as an object in your destination location. (In the DataSync console, you might also notice this prefix showing up as skipped or verified data.)
Skipped reports
A list of files, objects, and directories that DataSync finds in your source location but didn't attempt to transfer. The reasons DataSync skips data can depend on several factors, such as how you configure your task and storage system permissions. Here are some examples:
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There's a file that exists in your source and destination locations. The file in the source hasn't been modified since the previous task execution. Since you're only transferring data that has changed, DataSync doesn't transfer that file next time you run your task.
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An object that exists in both of your locations changes in your source. When you run your task, DataSync skips this object in your destination because your task doesn't overwrite data in the destination.
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DataSync skips an object in your source that's using an archival storage class and isn't restored. You must restore an archived object for DataSync to read it.
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DataSync skips a file, object, or directory in your source location because it can't read it. If this happens and isn't expected, check your storage's access permissions and make sure that DataSync can read what was skipped.
A skipped report includes the following details:
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The paths for skipped data
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The time when an item was skipped
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The reason it was skipped
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Whether an item was skipped successfully
Note
Skipped reports can be large when they include successes and errors, you configure your task to transfer only the data that has changed, and source data already exists in the destination.
Verified reports
A list of files, objects, and directories that DataSync attempted to verify the integrity of during your task execution. A verified data report includes the following details:
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The paths for verified data
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The time when an item was verified
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The reason for the verification error (if any)
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The source and destination SHA256 checksums (files only)
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Whether an item was successfully verified
Note the following about verified reports:
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When you configure your task to verify only transferred data, DataSync doesn't verify directories in some situations or files or objects that fail to transfer. In either case, DataSync doesn't include unverified data in this report.
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If you're using Enhanced mode, verification might take longer than usual if you're transferring large objects.
Deleted reports
A list of files, directories, and objects that were deleted during your task execution. DataSync generates this report only if you configure your task to delete data in the destination location that isn't in the source. A deleted data report includes the following details:
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The paths for deleted data
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Whether an item was successfully deleted
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The time when an item was deleted
Example task reports
The level of detail in your task report is up to you. Here are some example transferred data reports with the following configuration:
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Report type – Standard
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Report level – Successes and errors
Note
Reports use the ISO-8601 standard for the timestamp format. Times are in UTC and
measured in nanoseconds. This behavior differs from how some other task report
metrics are measured. For example, task
execution details, such as TransferDuration and
VerifyDuration, are measured in milliseconds.
Enhanced mode task reports use a somewhat different schema than Basic mode task reports. The following examples can help you know what to expect from your reports depending on the task mode you use.
- Example transferred data reports with success status
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The following reports show successful transfers for an object named
object1.txt. - Example transferred data reports with error status
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The following reports provide examples of when DataSync can't transfer an object named
object1.txt.
Limitations
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Individual task reports can't exceed 5 MB. If you're copying a large number of files, your task report might be split into multiple reports.
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There are situations when creating task reports can affect the performance of your data transfer. For example, you might notice this when your network connection has high latency and the files you're transferring are small or you're copying only metadata changes.
