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SCSICTL(8) NetBSD System Manager's Manual SCSICTL(8)
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scsictl -- a program to manipulate SCSI devices and busses
scsictl device command [arg [...]]
scsictl allows a user or system administrator to issue commands to and
otherwise control SCSI devices and busses. It is used by specifying a
device or bus to manipulate, the command to perform, and any arguments
the command may require. scsictl determines if the specified device is
an actual device or a SCSI bus automatically, and selects the appropriate
For commands which scsictl issues a SCSI command to the device directly,
any returned sense information will be decoded by scsictl and displayed
to the standard output.
The following commands are supported for SCSI devices:
debug level Set the debugging level for the given device; the following
flags are supported:
1 Show scsi commands, errors, data.
2 Routine flow tracking.
4 Internal info from routine flows.
8 Device specific debugging.
This option is only supported with kernels compiled with
defects [primary] [grown] [block|byte|physical]
Read the primary and/or grown defect lists from the speci-
fied device in block, byte from index, or physical sector
format. The default is to return both the primary and
grown defect lists in physical sector format. This command
is only supported on direct access devices.
format [blocksize [immediate]]
(Low level) format the named device. If the optional
blocksize parameter is provided, the device geometry will
be modified to use the specified blocksize. If this param-
eter is different form the Current or Default Mode Page 3
parameters, the device will update Mode Page 3 at the suc-
cessful completion of the Format. Device geometry may
change as a result of using a new device blocksize. When
the optional blocksize parameter is specified, the Defect
List on the drive will revert to the original primary
defect list created at the time of manufacture if avail-
able. The drive will usually recertify itself during the
Format and add any other defective blocks to the new Defect
List. Some disks may not support the ability to change the
blocksize and may enter a Degraded Mode when fed a Format
command of this type. If this happens the standard recov-
ery for the drive requires issuing a correct Format com-
mand, i.e. one without the blocksize parameter.
When the immediate parameter is also specified, the disk is
instructed to return from the format command right away.
It continues to format, and every ten seconds scsictl
issues a TEST UNIT READY command to check the associated
sense data. This associated sense data has a progress
indicator which indicates how far the format is progress-
ing. Note well that most SCSI disk drives prior to a few
years ago do not support this option.
identify Identify the specified device, displaying the device's SCSI
bus, target, and lun, as well as the device's vendor, prod-
uct, and revision strings.
reassign blkno [blkno [...]]
Issues a REASSIGN BLOCKS command to the device, adding the
specified blocks to the grown defect list. This command is
only supported on direct access devices.
release Send a ``RELEASE'' command to the device to release a
reservation on it.
reserve Send a ``RESERVE'' command to the device to place a reser-
vation on it.
reset Reset the device. This command is only supported for
devices which support the SCIOCRESET ioctl.
start Send a ``START'' command to the device. This is useful
typically only for disk devices.
stop Send a ``STOP'' command to the device. This is useful typ-
ically only for disk devices.
tur Send a ``TEST UNIT READY'' command to the device. This is
useful for generating current device status.
getcache Returns basic cache parameters for the device.
setcache none|r|w|rw [save]
Set basic cache parameters for the device. The cache may
be disabled (none), the read cache enabled (r), the write
cache enabled (w), or both read and write cache enabled
(rw). If the drive's cache parameters are savable, speci-
fying save after the cache enable state will cause the
parameters to be saved in non-volatile storage.
flushcache Explicitly flushes the write cache.
Set the highest speed that the optical drive should use for
reading data. The units are multiples of a single speed
CDROM (150 KB/s). Specify 0 to use the drive's fastest
getrealloc Returns automatic reallocation parameters for the device.
setrealloc none|r|w|rw [save]
Set automatic reallocation parameters for the device.
Automatic reallocation may be disabled (none), the auto-
matic read reallocation enabled (r), the automatic write
reallocation enabled (w), or both automatic read and write
reallocation enabled (rw). If the drive's automatic real-
location parameters are savable, specifying save after the
automatic reallocation enable state will cause the parame-
ters to be saved in non-volatile storage.
The following commands are supported for SCSI busses:
reset Reset the SCSI bus. This command is only supported if the
host adapter supports the SCBUSIORESET ioctl.
scan target lun
Scan the SCSI bus for devices. This is useful if a device
was not connected or powered on when the system was booted.
The target and lun arguments specify which SCSI target and
lun on the bus is to be scanned. Either may be wildcarded by
specifying the keyword ``any'' or ``all''.
detach target lun
Detach the specified device from the bus. Useful if a device
is powered down after use. The target and lun arguments have
the same meaning as for the scan command, and may also be
When scanning the SCSI bus, information about newly recognized devices is
printed to console. No information is printed for already probed
/dev/scsibus* - for commands operating on SCSI busses
ioctl(2), cd(4), ch(4), scsi(4), sd(4), se(4), ss(4), st(4), uk(4),
The scsictl command first appeared in NetBSD 1.4.
The scsictl command was written by Jason R. Thorpe of the Numerical Aero-
space Simulation Facility, NASA Ames Research Center.
NetBSD 9.3 November 19, 2016 NetBSD 9.3