dkctl
—
program to manipulate disks
dkctl |
device command
[arg [...]] |
dkctl
allows a user or system administrator to
manipulate and configure disks in various ways. It is used by specifying a
disk to manipulate, the command to perform, and any arguments the command may
require. device is the disk (wdN, sdN, ...) containing
the wedges unless noted otherwise. If dkctl
is called
without any command, it displays strategy, cache, and all of the wedges of the
specified device.
The following commands are supported:
addwedge
name startblk
blkcnt ptype
- Define a “wedge” on the specified disk starting at block
number startblk and spanning
blkcnt blocks. You need to create the partition
first with fdisk(8) or
gpt(8),
dkctl
will just name it. The wedge will have the
volume name name and the partition type
ptype. Valid choices for ptype would be
unused, swap,
ffs, lfs,
ext2fs, cd9660,
ados, hfs,
msdos, filecore,
raidframe, ccd,
appleufs, ntfs, and
cgd.
The device name of the virtual block device assigned to the
wedge will be displayed after the wedge has been successfully created.
See dk(4) for more information
about disk wedges.
badsector
flush | list |
retry
- Used for managing the kernel's bad sector list for
wd(4) devices. The software bad
sector list is only maintained if the option
“WD_SOFTBADSECT” was specified on kernel configuration.
- flush
- Clears the in kernel list of bad sectors.
- list
- Prints out the list of bad sector ranges recorded by the kernel.
- retry
- Flushes the in kernel list and then retries all of the previously
recorded bad sectors, causing the list to self update. This option
can only be used with character devices.
delwedge
dk
- Delete the wedge specified by its device name dk
from the specified disk.
getcache
- Get and display the cache enables for the specified device.
getwedgeinfo
- Display information about the specified disk wedge.
device in this case is the wedge name.
keeplabel
[yes | no]
- Specify to keep or drop the in-core disklabel on the last close of the
disk device. (Keep if yes is specified, drop if
no is specified.)
listwedges
[-e
] [-q
]
- List all of the wedges configured on the specified disk. With
-e
exit with a non-zero exit status if there are
no wedges configured on that disk. With -q
(quiet
mode) there is no output related to the wedges that do, or do not,
exist.
makewedges
- Delete all wedges configured on the specified disk, and autodiscover the
wedges again. Wedges that are in use are not deleted and conflicting or
overlapping wedges are not created. You need to list wedges to find out
what has changed.
setcache
none | r |
w | rw
[save]
- Set the cache enables for the specified device. The enables are as
follows:
- none
- Disable all caches on the disk.
- r
- Enable the read cache, and disable all other caches on the disk.
- w
- Enable the write cache, and disable all other caches on the disk.
- rw
- Enable both the read and write caches on the disk.
- save
- If specified, and the cache enables are savable, saves the cache
enables in the disk's non-volatile parameter storage.
strategy
[name]
- Get and set the disk I/O scheduler (buffer queue strategy) on the drive.
If you do not provide a name argument, the currently
selected strategy will be shown. To set the bufq strategy, the
name argument must be specified.
name must be the name of one of the built-in kernel
disk I/O schedulers. To get the list of supported schedulers, use the
following command:
$ sysctl kern.bufq.strategies
synccache
[force]
- Causes the cache on the disk to be synchronized, flushing all dirty write
cache blocks to the media. If force is specified,
the cache synchronization command will be issued even if the kernel does
not believe that there are any dirty cache blocks in the disk's
cache.
Note: The addwedge
and
delwedge
commands only modify the in-kernel
representation of disks; for modifying information on the disks themselves,
refer to fdisk(8) or
gpt(8).
The dkctl
command first appeared in
NetBSD 1.6.
The dkctl
command was written by Jason
R. Thorpe of Wasabi Systems, Inc.