I think he means that.
I remeber when I inserted 2 disks, the available screen option are :
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mkid 發表於 2013-11-4 14:12 
It is not a simple task, I think no NAS support this
upgrade from Single Disk > RAID 1 > RAID 5 > RAID 6 is easy
downgrade almost impossible unless you manually in command line do it, and reconfigure the settings |