Here's what SMART tells me the serial number is:
=== START OF INFORMATION SECTION ===
Device Model: Hitachi HDS721010CLA332
Serial Number: JP2940HQ3ZY7KH
Firmware Version: JP4OA3EA
User Capacity: 1,000,204,886,016 bytes
Device is: Not in smartctl database [for details use: -P showall]
ATA Version is: 8
ATA Standard is: ATA-8-ACS revision 4
Local Time is: Mon Apr 8 17:47:02 2013 PDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
When looking at the actual drive you will see "HQ3ZY7KH" which omits the beginning "JP2940" that SMART reports.
This is the case with other manufacturers too, sometimes you have to add or remove things from what SMART gives you. It should be mandatory that what appears as the SERIAL# in the firmware is the same as the sticker.
When you have a lot of drives to deal with it's easier and quicker to use a program to pull the serial rather than opening the case(s) of multiple computers.
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