H3C Technologies H3C S5120 Series Switches - Manual (Page 607)

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To do… Use the command… Remarks
Restore the space of a storage
medium
fixdisk device
Optional
Available in user view
Format a storage medium format device
Optional
Available in user view
When you format a storage medium, all the files stored on it are erased and cannot be restored. In
particular, if there is a startup configuration file on the storage medium, formatting the storage medium
results in loss of the startup configuration file.
Displaying and Maintaining the NAND Flash Memory
Featured with high storage capacity, low cost, and fast write speed, the NAND flash memory has
become a preferred memory of new products. The physical space of the NAND flash memory is
logically divided into multiple blocks, each of which is subdivided into multiple pages. The NAND flash
memory is erased on a block basis and read on a page basis; the memory spaces are allocated on a
page basis.
Displaying and repairing bad blocks
It is common to have bad blocks when an NAND flash memory is shipped from the factory. Bad block
ratio varies with products of different vendors. The frequently used area of the memory goes bad easily.
Bad blocks cannot be used to store data, and the file system has to skip the bad blocks when it allocates
storage spaces to files. You can get the locations of bad blocks and repair them through command lines.
Follow these steps to display and repair bad blocks:
To do… Use the command… Remarks
Display the number and
location of bad blocks in the
NAND flash memory
display nandflash
badblock-location Required
Available in any view
Repair bad blocks fixdisk device
Required
Available in user view
Checking files
After files are written to the NAND flash memory, you can use the following two commands together to
check the content of these files.
Follow these steps to check files:
To do… Use the command… Remarks
Display the space distribution
of the specified file in the NAND
flash memory
display nandflash
file-location filename
Available in any view