NAME    [Toc]    [Back]

       badsect - Creates files to contain bad sectors

SYNOPSIS    [Toc]    [Back]

       /usr/sbin/badsect bbdir sector...

DESCRIPTION    [Toc]    [Back]

       The  badsect command makes a file to contain a bad sector.
       Normally, bad sectors are made inaccessible by  the  standard
  formatter, which provides a forwarding table for bad
       sectors to the driver. If a driver supports the bad blocking
  standard, it is preferable to use that method to isolate
 bad blocks because the bad block forwarding makes the
       disk  appear  perfect,  and  such disks can then be copied
       with dd(1). The technique used by  badsect  is  also  less
       general  than bad block forwarding, as badsect cannot make
       amends for bad blocks in the i-list of file systems or  in
       swap areas.

       On some disks, adding a sector that is suddenly bad to the
       bad sector table currently requires  the  running  of  the
       standard  formatter.  Thus, to deal with a newly bad block
       or on disks where the drivers  do  not  support  the  badblocking
 standard, badsect can be used to good effect.

       Use the badsect command on a quiet file system in the following
 way: Mount the file system and change to  its  root
       directory.  Make a directory BAD there.  Run badsect, giving
 as argument the BAD directory followed by all the  bad
       sectors you wish to add.  (The sector numbers must be relative
 to the beginning of the file system, as reported  in
       console  error  messages.)  Change back to the root directory,
 unmount the file system, and run fsck(8) on the file
       system.  The bad sectors should show up in two files or in
       the bad sector files and the free list.  Have fsck  remove
       files  containing  the  offending  bad sectors, but do not
       have it remove the BAD/nnnnn files.  This  operation  will
       leave the bad sectors in only the BAD files.

       The  badsect  command works by giving the specified sector
       numbers in a mknod(2) system  call,  creating  an  illegal
       file whose first block address is the block containing bad
       sector and whose name is the bad sector number.  When fsck
       discovers  the  file,  it  will  ask "HOLD BAD BLOCK?"  An
       affirmative response will cause fsck to convert the  inode
       to a regular file containing the bad block.

RESTRICTIONS    [Toc]    [Back]

       If more than one of the sectors comprised by a file system
       fragment are bad, you should specify only one to  badsect,
       as  the  blocks in the bad sector files cover all the sectors
 in a file system fragment.

ERRORS    [Toc]    [Back]

       The badsect command refuses to attach a block that resides
       in  a critical area or is out of range of the file system.
       A warning is issued if the block is already in use.

SEE ALSO    [Toc]    [Back]

       Commands: fsck(8)



                                                       badsect(8)