Seagate ST9900605SS ユーザーズマニュアル

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Savvio 10K.5 SAS Product Manual, Rev. D
9.2.2
Locking SP
The Locking SP controls read/write access to the media and the cryptographic erase feature. Access to the 
Locking SP is available using the BandMasterX or EraseMaster passwords. Since the drive owner can define 
up to 16 data bands on the drive, each data band has its own password called BandMasterX where X is the 
number of the data band (0 through 15).
9.2.3
Default password
When the drive is shipped from the factory, all passwords are set to the value of MSID. This 32-byte random 
value is printed on the drive label and it can be read by the host electronically over the I/O. After receipt of the 
drive, it is the responsibility of the owner to use the default MSID password as the authority to change all other 
passwords to unique owner-specified values.
9.3
Random number generator (RNG)
The drive has a 32-byte hardware RNG that it is uses to derive encryption keys or, if requested to do so, to pro-
vide random numbers to the host for system use, including using these numbers as Authentication Keys (pass-
words) for the drive’s Admin and Locking SPs.
9.4
Drive locking
In addition to changing the passwords, as described in Section 9.2.3, the owner should also set the data 
access controls for the individual bands. 
The variable "LockOnReset" should be set to "PowerCycle" to ensure that the data bands will be locked if 
power is lost. This scenario occurs if the drive is removed from its cabinet. The drive will not honor any data 
read or write requests until the bands have been unlocked. This prevents the user data from being accessed 
without the appropriate credentials when the drive has been removed from its cabinet and installed in another 
system.
When the drive is shipped from the factory, the firmware download port is unlocked.
9.5
Data bands
When shipped from the factory, the drive is configured with a single data band called Band 0 (also known as 
the Global Data Band) which comprises LBA 0 through LBA max. The host may allocate Band1 by specifying a 
start LBA and an LBA range. The real estate for this band is taken from the Global Band. An additional 14 Data 
Bands may be defined in a similar way (Band2 through Band15) but before these bands can be allocated LBA 
space, they must first be individually enabled using the EraseMaster password.
Data bands cannot overlap but they can be sequential with one band ending at LBA (x) and the next beginning 
at LBA (x+1).
Each data band has its own drive-generated encryption key and its own user-supplied password. The host may 
change the Encryption Key (see Section 9.6) or the password when required. The bands should be aligned to 
4K LBA boundaries.
9.6
Cryptographic erase
A significant feature of SEDs is the ability to perform a cryptographic erase. This involves the host telling the 
drive to change the data encryption key for a particular band. Once changed, the data is no longer recoverable 
since it was written with one key and will be read using a different key. Since the drive overwrites the old key 
with the new one, and keeps no history of key changes, the user data can never be recovered. This is tanta-
mount to an instantaneous data erase and is very useful if the drive is to be scrapped or redispositioned.