ADDBADSEC(8) Maintenance Procedures ADDBADSEC(8)

NAME

addbadsec - map out defective disk blocks

SYNOPSIS

addbadsec [-p] [-a blkno [blkno]...] [-f filename] raw_device

DESCRIPTION

addbadsec is used by the system administrator to map out bad disk blocks.
Normally, these blocks are identified during surface analysis, but
occasionally the disk subsystem reports unrecoverable data errors
indicating a bad block. A block number reported in this way can be fed
directly into addbadsec, and the block will be remapped. addbadsec will
first attempt hardware remapping. This is supported on SCSI drives and
takes place at the disk hardware level. If the target is an IDE drive,
then software remapping is used. In order for software remapping to
succeed, the partition must contain an alternate slice and there must be
room in this slice to perform the mapping.


It should be understood that bad blocks lead to data loss. Remapping a
defective block does not repair a damaged file. If a bad block occurs to
a disk-resident file system structure such as a superblock, the entire
slice might have to be recovered from a backup.

OPTIONS

The following options are supported:

-a
Adds the specified blocks to the hardware or software map. If more
than one block number is specified, the entire list should be
quoted and block numbers should be separated by white space.


-f
Adds the specified blocks to the hardware or software map. The bad
blocks are listed, one per line, in the specified file.


-p
Causes addbadsec to print the current software map. The output
shows the defective block and the assigned alternate. This option
cannot be used to print the hardware map.

OPERANDS

The following operand is supported:

raw_device
The address of the disk drive (see FILES).

FILES

The raw device should be /dev/rdsk/c?[t?]d?p0. See disks(8) for an
explanation of SCSI and IDE device naming conventions.

SEE ALSO

attributes(7), disks(8), diskscan(8), fdisk(8), fmthard(8), format(8)

NOTES

The format(8) utility is available to format, label, analyze, and repair
SCSI disks. This utility is included with the addbadsec, diskscan(8),
fdisk(8), and fmthard(8) commands available for x86. To format an IDE
disk, use the DOS "format" utility; however, to label, analyze, or
repair IDE disks on x86 systems, use the Solaris format(8) utility.


February 24, 1998 ADDBADSEC(8)