NAME [Toc] [Back]
scsictl - control a SCSI device
SYNOPSIS [Toc] [Back]
scsictl [-akq] [-c command]... [-m mode[=value]]... device
scsictl [-o ola_params]...
scsictl -p pr_clear key device
DESCRIPTION [Toc] [Back]
The scsictl command provides a mechanism for controlling a SCSI
device. It can be used to query mode parameters, set configurable
mode parameters, and perform SCSI commands. The operations are
performed in the same order as they appear on the command line.
The second form, as shown above, supports the online addition of a
supported SCSI card to a system. This option cannot be used with any
other options available for this command.
scsictl command can be used to clear persistent reservation from a
device, as shown in the third form above, using the -p option.
device specifies the character special file to use.
Options [Toc] [Back]
scsictl recognizes the following options.
-a Display the status of all mode parameters available,
separated by semicolon-blank (;) or newline.
Cause the device to perform the specified command.
command can be one of the following:
erase For magneto-optical devices that
support write without erase, this
command can be used to pre-erase the
whole surface to increase data
throughput on subsequent write
operations. This command maintains
exclusive access to the surface
during the pre-erasure.
sync_cache For devices that have an internal
write cache, this command causes the
device to flush its cache to the
domain_val Domain validation allows the user to
check the quality of transmissions
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across the bus and helps to find
problems like faulty and missing
terminators, bad components, etc.
This command is only valid for
Ultra160 and later devices. If any
errors encountered during domain
validation, they will be logged in
get_bus_parms This command displays information
about limits and negotiable
parameters of a bus.
get_lun_parms This command displays information
about limits and negotiable
parameters of a physical or a virtual
get_target_parms This command displays information
about limits and negotiable
parameters of a target peripheral
reset_target This command causes a target reset
task management function to be sent
to the associated target.
reset_bus This command causes the system to
generate a SCSI bus reset condition
on the associated bus. A SCSI bus
reset condition causes all devices on
the bus to be reset (including
clearing all active commands on all
-k Continue processing arguments even after an error is
detected. The default behavior is to exit immediately
when an error is detected.
Command line syntax is always verified for correctness,
regardless of the -k option. Improper command line
syntax causes scsictl to exit without performing any
operations on the device.
-m mode Display the status of the specified mode parameter.
mode can be one of the following:
immediate_report For devices that support immediate
reporting, this mode controls how the
device responds to write requests.
If immediate report is enabled (1),
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write requests can be acknowledged
before the data is physically
transferred to the media. If
immediate report is disabled (0), the
device is forced to await the
completion of any write request
before reporting its status.
ir Equivalent to immediate_report.
queue_depth For devices that support a queue
depth greater than the system
default, this mode controls how many
I/Os the driver will attempt to queue
to the device at any one time. Valid
values are (1-255). Some disk
devices will not support the maximum
queue depth settable by this command.
Setting the queue depth in software
to a value larger than the disk can
handle will result in I/Os being held
off once a QUEUE FULL condition
exists on the disk.
Set the mode parameter mode to value. The available
mode parameters and values are listed above.
Mode parameters that take only a binary value (1 or 0)
can also be specified as either on or off,
Currently this option supports only the following
ola_params This command should be followed by
five arguments namely, hw_path,
scsi_id, width, period, and offset.
Actual values of scsi_id, width,
period and offset are decided by the
hardware. If the hardware is not
capable of supporting the requested
values, they will be brought to the
maximum capability of the card. A
value of -1 may be specified for
scsi_id, width, period and offset in
order to use the hardware default
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Note: This command does not validate
any of the arguments passed.
Therefore, it does not show any
output upon successful completion.
-q Suppress the labels that are normally printed when mode
parameters are displayed. Mode parameter values are
printed in the same order as they appear on the command
line, separated by semicolon-blank (; ) or newline.
-p pr_clear key device
The scsictl command with the -p pr_clear option can be
used to clear the persistent reservation from a device.
This command can not be used with any other options or
commands available for the scsictl command.
This command should be followed by two arguments: key
and device. key is a string of characters which was
used while setting persistent reservation. This key
can be in any of the following two formats:
(a) Text format: can contain any of alphanumeric
characters. In this format length of the key
should not exceed 8 characters.
(b) Hex format: preceded by 0x or 0X, can contain any
of hexadecimal digit. In this format length of the
string should not exceed 18 characters in total
(including 0x or 0X).
Mode parameters and commands need only be specified up to a unique
prefix. When abbreviating a mode parameter or command, at least the
first three characters must be supplied.
DIAGNOSTICS [Toc] [Back]
Diagnostic messages are generally self-explanatory.
EXAMPLES [Toc] [Back]
To display all the mode parameters, turn immediate_report on, and
redisplay the value of immediate_report:
scsictl -a -m ir=1 -m ir /dev/rdsk/c0t6d0
producing the following output:
immediate_report = 0; queue_depth = 8; immediate_report = 1
The same operation with labels suppressed:
scsictl -aq -m ir=1 -m ir /dev/rdsk/c0t6d0
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produces the following output:
0; 8; 1
To clear persistent reservation from a device:
scsictl -p pr_clear key /dev/rdsk/c0t6d0
WARNINGS [Toc] [Back]
Not all devices support all mode parameters and commands listed above.
Changing a mode parameter may have no effect on such a device.
Issuing a command that is not supported by a device can cause an error
message to be generated.
scsictl is not supported on sequential-access devices using the tape
The immediate_report mode applies to the entire device; the section
number of the device argument is ignored.
To aid recovery, immediate reporting is not used for writes of file
system data structures that are maintained by the operating system,
writes to a hard disk (but not a magneto-optical device) through the
character-device interface, or writes to regular files that the user
has made synchronous with O_SYNC or O_DSYNC (see open(2) and
DEPENDENCIES [Toc] [Back]
When the system is rebooted, the disc3 driver always resets the value
of the immediate_report mode parameter to off. If ioctl() or scsictl
is used to change the setting of immediate reporting on a SCSI device,
the new value becomes the default setting upon subsequent
configuration (e.g., opens) of this device and retains its value
across system or device powerfail recovery. However, on the next
system reboot, the immediate-report mode parameter is again reset to
the value of the tunable system parameter, default_disk_ir. This is
set using the kctune(1M) command.
If ioctl() or scsictl is used to change the setting of immediate
reporting on a SCSI device, the new value becomes the default setting
upon subsequent configuration (e.g., opens) of this device until the
"last close" of the device, that is, when neither the system nor any
application has the device open (for example, unmounting a file system
via umount and then mounting it again via mount (see mount(1M)). On
the next "first open", the immediate-report mode parameter is again
reset to the value of the tunable system parameter, default_disk_ir.
This is set using the kctune(1M) command.
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SEE ALSO [Toc] [Back]
diskinfo(1M), fcntl(2), kctune(1M), open(2).
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