Seagate ST91000641SS ユーザーズマニュアル
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Constellation.2 SAS Product Manual, Rev. H
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 can only be read by the host electronically over the interface. After receipt of the drive, it is the responsi-
bility of the owner to use the default MSID password as the authority to change all other passwords to unique
owner-specified values.
value can only be read by the host electronically over the interface. After receipt of the drive, it is the responsi-
bility 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.
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.
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. In addition "ReadLockEnabled" and "WriteLockEnabled" must be set to true in the locking table in
order for the bands "LockOnReset" setting of "PowerCycle" to actually lock access to the band when a "Power-
Cycle" event occurs. 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.
power is lost. In addition "ReadLockEnabled" and "WriteLockEnabled" must be set to true in the locking table in
order for the bands "LockOnReset" setting of "PowerCycle" to actually lock access to the band when a "Power-
Cycle" event occurs. 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.
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).
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.
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.
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.
9.7
Authenticated firmware download
In addition to providing a locking mechanism to prevent unwanted firmware download attempts, the drive also
only accepts download files which have been cryptographically signed by the appropriate Seagate Design
Center.
only accepts download files which have been cryptographically signed by the appropriate Seagate Design
Center.