This SCP prevents users or roles in any affected account from deleting Amazon EC2 flow logs or CloudWatch log groups or log streams.

 
Tags
Flow Logs
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Action": [
                "ec2:DeleteFlowLogs",
                "logs:DeleteLogGroup",
                "logs:DeleteLogStream"
            ],
            "Resource": "*",
            "Effect": "Deny"
        }
    ]
}
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