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Remediation Steps:
Perform following to change the master username configure encryption for Redshift :
Login to the AWS Management Console at https://console.aws.amazon.com.
Navigate to Redshift console.
In the navigation pane, choose CLUSTERS, then choose the cluster that you want to modify for encryption.
For Actions, choose Modify to display the configuration page.
In the Database configuration section, choose the setting for Encryption Use AWS KMS, then choose KMS key id.
Choose Modify cluster.
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