There lies the answer! We have a requirement of recreating the cluster in case we accidentally delete entire data or if we loose our master. In such a case the reliable backup can only be taken if your HDFS data does not reside on the root devices. A reliable backup of the root device cannot be taken without rebooting the device. Furthermore it's stored as an AMI which mean you have to create a new AMI every day and delete the old one. This means to solve all of our problems we need HBase installation and data both stored on attached EBS volumes that are not the root devices.
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