The Copy back feature of Adaptec Array Controller is a good feature, it's a useful feature especially you'd like to have your disk order keep the same after rebuild.

Default, it's disabled, I leave this one seperated from Arcconf Command Examples on Linux

Here is the Syntax

# arcconf copyback

 Usage: COPYBACK <Controller#> <on|off>

 Toggles the controller copy back mode, which attempts
 to keep drives in the original slot order after rebuilds

    on  : Turns copyback mode on.
    off : Turns copyback mode off.


So, as it says, when you have hotspare disk and the failed disk replaced, after rebuild, the controller will copy data on hot spare back to the origional disk slot, thus, the array slot order keeps the same.

Here is an example output

# arcconf GETCONFIG 1 AD
Controllers found: 1
Controller information
   Controller Status                        : Okay
   Channel description                      : SAS/SATA
   Controller Model                         : IBM ServeRAID 8k    
   Controller Serial Number                 : 401DE68
   Physical Slot                            : 0
   Installed memory                         : 256 MB
   Copyback                                 : Disabled
   Data scrubbing                           : Enabled
   Automatic Failover                       : Enabled
   Defunct disk drive count                 : 0
   Logical drives/Offline/Critical          : 2/0/0