IBM DBCA-204860 - Travelstar 4.8 GB Hard Drive, Технические характеристики

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10.7.4.4 User Password Lost
If the User Password is forgotten and High level security is set, the system user can't access any data.
However the device can be unlocked using the Master Password.
If a system user forgets the User Password and Maximum security level is set, data access is impossible.
However the device can be unlocked using the Security Erase Unit command to unlock the device and erase
all user data with the Master Password.
U s e r P a s s w o r d L o s t
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L E V E L ? H i g h
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> U n l o c k C M D w i t h M a s t e r P a s s w o r d
M a x i m u m
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E r a s e P r e p a r e C o m m a n d N o r m a l o p e r a t i o n
E r a s e U n i t C o m m a n d
w i t h M a s t e r P a s s w o r d
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N o r m a l o p e r a t i o n b u t d a t a l o s t
Figure 52. Password Lost
10.7.4.5 Attempt limit for SECURITY UNLOCK command
The SECURITY U N L O C K command has an attempt limit. The purpose of this attempt limit is to prevent
that someone attempts to unlock the drive by using various passwords many times.
The device counts the password mismatch. If the password does not match, the device counts it up without
distinguishing the Master password and the User password.
If the count reaches 5, E X P I R E bit(bit 4) of
Word 128 in Identify Device information is set, and then SECURITY ERASE U N I T command and SECU-
R I T Y U N L O C K command are aborted until a hard reset or a power off. The count and E X P I R E bit are
cleared after a power on reset or a hard reset.
General Operation Descriptions
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