sg_raw - sends an arbitrary SCSI command to a device
sg_raw [OPTIONS] DEVICE CDB0 CDB1 ...
This utility sends an arbitrary SCSI command (between 6 and 256 bytes) to
the DEVICE. There may be no associated data transfer; or data may be
read from a file and sent to the DEVICE; or data may be received from
the DEVICE and then displayed or written to a file. If supported
by the pass through, bidirectional commands may be sent (i.e. containing
both data to be sent to the DEVICE and received from the
The SCSI command may be between 6 and 256 bytes long. Each command byte is
specified in plain hex format (00..FF) without a prefix or suffix. See
EXAMPLES section below.
The commands pass through a generic SCSI interface which is implemented
for several operating systems including Linux, FreeBSD and Windows.
Arguments to long options are mandatory for short options as well.
Dump data in binary form, even when writing to stdout.
Display usage information and exit.
Read data from IFILE instead of stdin. This option is ignored if
--send is not specified.
Skip the first LEN bytes of the input file or stream. This option
is ignored if --send is not specified.
Don't display SCSI Sense information.
Write data received from the DEVICE to OFILE. The data is
written in binary. By default, data is dumped in hex format to stdout.
If OFILE is '-' then data is dumped in binary to stdout.
This option is ignored if --request is not specified.
Expect to receive up to RLEN bytes of data from the DEVICE.
RLEN may be suffixed with 'k' to use kilobytes (1024 bytes) instead
Open DEVICE read-only. The default (without this option) is to open
Read SLEN bytes of data, either from stdin or from a file, and send
them to the DEVICE.
Wait up to SEC seconds for command completion (default: 20).
Note that if a command times out the operating system may start by
aborting the command and if that is unsuccessful it may attempt
to reset the device.
Increase level of verbosity. Can be used multiple times.
Display version and license information and exit.
The sg_inq utility can be used to send an INQUIRY command to a device
to determine its peripheral device type (e.g. '1' for a streaming
device (tape drive)) which determines which SCSI command sets a device
should support (e.g. SPC and SSC). The sg_vpd utility probes the Vital
Product Pages of a devices which may contain useful information.
The ability to send more than a 16 byte CDB (in some cases 12 byte CDB)
may be restricted by the pass-through interface, the low level driver
or the transport.
These examples, apart from the last one, use Linux device names. For
suitable device names in other supported Operating Systems see the
sg3_utils(8) man page.
sg_raw /dev/scd0 1b 00 00 00 02 00
Eject the medium in CD drive /dev/scd0.
sg_raw -r 1k /dev/sg0 12 00 00 00 60 00
Perform an INQUIRY on /dev/sg0 and dump the response data (up to
1024 bytes) to stdout.
Showing an example of writing 512 bytes to a sector on a disk
is a little dangerous. Instead this example will read i512.bin (assumed
to be 512 bytes long) and use the SCSI WRITE BUFFER command to send
it to the "data" buffer (that is mode 2). This is a safe operation.
This will use the SCSI READ BUFFER command to read 512 bytes from
the "data" buffer (i.e. mode 2) then write it to the o512.bin file.
When used in conjunction with the previous example, if both commands
work then 'cmp i512.bin o512.bin' should show a match.
This is a bidirectional XDREADWRITE(10) command being sent via a Linux
bsg device. Note that data is being read from "urandom.bin" and sent
to the device (data-out) while resulting data (data-in) is placed
in the "out.bin" file. Also note the length of both is 512 bytes
which corresponds to the transfer length of 1 (block) in the cdb (i.e.
the second last byte).
This example is from Windows and shows a ATA STANDBY IMMEDIATE command
being sent to PhysicalDrive1. That ATA command is contained within
the SCSI ATA PASS-THROUGH(12) command (see the SAT or SAT-2 standard at
http://www.t10.org). Notice that the STANDBY IMMEDIATE command does not
send or receive any additional data, however if it fails sense data
should be returned and displayed.
The exit status of sg_raw is 0 when it is successful. Otherwise see
the sg3_utils(8) man page.