Dear fordem,
thanks for the esplanation about the flag of rebuild driver non flaggable: I had a RAID 1 so is correct, at this point that was not flaggable.
Again, the drives are the same, so I was quite sure to have only a RAID 1.
At present my situation with the new driver is:
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HARD DRIVE INFO :
Total Drive(s): 2
Volume Name: Volume_1
Volume Type: RAID 1
Sync Time Remaining: 223.2 minute(s)
Total Hard Drive Capacity: 1474368 MB
Used Space: 488757 MB
Unused Space: 985610 MB
Volume Name: Volume_2
Volume Type: JBOD
Total Hard Drive Capacity: 2671 MB
Used Space: 3 MB
Unused Space: 2667 MB
PHYSICAL DISK INFO :
Slot Vendor Model Serial Number Size
Right Seagate ST31500341AS 9VS4XJCC 1500 G
Left Seagate ST31500341AS 9VS2Z6TQ 1500 G
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So seems to be what you say: I just have a JBOD of 2671 MB; the other capacity is all in RAID 1.
To bakup the data is not so simple (I have to pass via FTP on a PC and then save all on a USB driver, will be slow and... expensive

)
thanks a lot
RRE