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Perform following to update DocumentDB master user namecluster snapshot encryption:
Login to the AWS Management Console at https://console.aws.amazon.com.
Navigate to DocumentDB console.
In the Navigation pane, click on Snapshots.
Click on the Snapshot to encrypt, click Actions button.
Under Actions, choose Copy Snapshot.
Choose your Destination Region, and then enter your New DB Snapshot Identifier.
Select Copy Tags if needed.
Under Encryption, select Enable Encryption.
Select your Master Key from the list, and then choose Copy Snapshot.
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