DISK(8) UNIX Programmer's Manual DISK(8)
NAME
disk - disk initialization and diagnosis
SYNOPSIS
/usr/etc/disk [ option flags ] [ action flags ] raw-device
DESCRIPTION
The disk utility program can be used to initialize, inspect,
repair, and configure optical, floppy and SCSI disks.
The option flags are used with the -i action flag to specify
certain parameters when initializing a disk:
-h hostname
Specifies a hostname to be stored in the disk
label. The actual hostname of a machine is not
determined by the disk label, but in the case of
removable optical media this field may be set for
informational purposes to indicate which machine
the disk belongs to.
-l labelname
The labelname of a disk is printed in the message
log when the system boots. For optical media this
is also the name used as the mount point in the /
directory when the disk is automounted.
-t disk_type
The disk configuration information in /etc/disktab
is named by an identifier called the disk type. By
default, when the disk program is run it will
attempt to determine the proper disk type to use.
Use this flag to override the default. This is
used to reinitialize a disk using a different set
of configuration parameters from /etc/disktab
(e.g. a different number and/or size of filesystem
partition(s)).
The action flags are used to perform a specific command in
the disk program (only one may be specified):
-i This flag will initialize a disk including writing
out a new disk label containing information about
the host name, label name and information found in
/etc/disktab. A boot program will be installed
onto the boot block area of the disk from the file
/usr/standalone/boot. If specified in the confi-
guration information in /etc/disktab, the initial-
ize flag will also build empty UNIX filesystems on
the disk. The initialize flag will destroy all
data on the disk. WARNING: Don't initialize a
mounted device. Example: "/etc/disk -h myhost -l
mydisk -i /dev/rod0a"
-e This flag will eject ejectable media. No attempt
is made to unmount the filesystems on this disk
before ejecting.
-b The boot program in /usr/standalone/boot will be
written onto the boot block area of the disk.
-B Same as -b, except that it takes as an argument
the pathname of the file containing data to be
written onto the boot block area of the disk.
-p partitionsize
The first partition of a two-partition disk will
be partitionsize, and the second partition uses
the remainder of the disk. The partitionsize is
in units of the native blocksize of the device
(minimum 1K). The -p option only has meaning when
used with -i.
-q The default disk type information returned by the
device driver for this disk will be printed. This
flag is used by the Builddisk application to
determine what kind of disk is present.
-s If the device driver keeps any special statistics
for the disk they will be printed with this flag.
-F This flag formats the disk.
-H hostname
This flag can be used to change the hostname field
of the disk label without disturbing other fields
in the label.
-L labelname
This flag can be used to change the labelname
field of the disk label without disturbing other
fields in the label.
If no action flags are specified the program operates in an
interactive mode. In interactive mode type the interrupt
character at any time to abort the current command. Typing
'?' will list the available commands. Many of the commands
will prompt for additional arguments or sub-commands. There
are many interactive commands in addition to the ones
described by the option flags above:
read, write, verify, rw, rwr
These commands will read, write and verify data on
the disk. All block numbers used in these com-
mands are absolute disk block numbers and do not
correspond to block numbers reported from the
filesystem. No bad sector forwarding or additions
are performed with these commands. On an optical
disk, these commands can be used to write a sector
that has become unreadable due to an uncorrectable
ECC errors. WARNING: These commands may destroy
disk data.
look, set These commands may be used to inspect and modify
the data buffers used in the read and write com-
mands described above.
abort This command toggles whether an error will stop
the read and write commands described above.
label This command is used to print and change informa-
tion in the disk label. To change only the host-
name or labelname fields use the -H hostname or -L
labelname action flags described earlier.
bad Use this command to display and edit the bad block
table maintained on optical disks.
bitmap Use this command to display and edit the sector
status bitmap maintained on optical disks.
scan The scan command sequentially searches the disk
for file system super blocks and prints the file
system block number where they are found. This
information is essential if the primary super
block of a file system is damaged and one needs to
specify an alternate super block location to the
file system check program fsck but one does not
know which block number to specify. (e.g. "fsck
-bnnn /dev/rod0a" where "nnn" is the block number
of the alternate super block). A list of these
block numbers is produced when a file system is
initialized with the newfs command, but this list
usually isn't around when needed.
FILES
/etc/disktab for disk geometry and partition layout
information
/usr/standalone/boot
the default program written onto the
boot block area
SEE ALSO
disktab(5)
BUGS
Like all low-level diagnostics written early in the life of
a new computer, this program exhibits evolutionary develop-
ment. Some features may be difficult to understand or not
work exactly as advertised.