Fujitsu MAT3300FC 사용자 설명서

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Disk Media Management 
 
6-8 
C141-C008 
(3)  Reading and verification of data 
Issue the READ, READ EXTENDED or VERIFY command and verify that the 
data written to the disk media in item (2) were read correctly. 
To verify reading of data, it is recommended that reading of the same data block 
be done at lease 2 times, but the number of times verification is performed is 
determined by the conditions on the system.  If reading of all data is completed 
normally, it can be recognized that use of that data block can be used normally. 
(4) Error verification 
When an error related to the disk media (Sense Key = 3:  MEDIUM ERROR) 
occurs during writing of the data pattern (see item (2)) or verification of data 
reading (see item (3)), reexecute the rewriting and reading verification 
combination (two times) at least 8 times. 
When the same type of error occurs even once during reexecution, it is 
recommended that the INIT treat that data block as a defective block.  If the 
reexecution of verification is completed normally every time, it should be 
regarded that that data block can be used normally. 
6.4   Alternate Block Allocation Processing 
If errors on the disk media which cannot be recovered from are detected, or if a 
recoverable error occurs repeatedly in the same data block, it is necessary for the 
INIT to allocate an alternate block for the data block where the error occurred 
using the REASSIGN BLOCKS command.  The procedure for alternate block 
processing is shown below. 
 
An attempt will be made to copy the contents of the data area of the 
logical data block specified in the "Defect Data" list to the alternate 
block allocated by this command, but in some cases, the data cannot 
be copied.  Confirmation of the contents of data in the allocated 
alternate block, saving of data before issuing this command and 
restoring of data after executing this command are the responsibility 
of the INIT. 
 
1)  Verify data blocks in accordance with the procedure in Section 6.3 for data 
blocks where error occur.  When such a data block is judged to be normal, 
alternate block allocation need not be implemented.  In this case, rewrite the 
original data to that data block if necessary.  When the data block is judged to 
be defective, implement the processing in item 2) and after. 
2)  Specify a logical block address for a data block which is judged to be 
defective and issue the REASSIGN BLOCKS command.