Just some steps to adding new block of drive to my EC2, but aware that there is some different on new linux kernel. In AWS, you still can add /dev/sdb but appear as /dev/xvdb. If you directly added as /dev/xvdb, you will get error. So think Amazon has done some scripting to ease our life.
So first run some checking to see what drives already used in your OS.
Then on AWS, create and attach the new volume without overlap with the existing one.
Go back to my EC2 terminal interface.
mke2fs -F -j /dev/xvde mkdir /mnt/backup mount /dev/xvde /mnt/backup
Then start to back up my things by follow instruction here