sdparm - access SCSI modes pages; read VPD pages; send simple SCSI commands.
sdparm [--all] [--dbd] [--examine]
[--flexible] [--get=STR] [--hex] [--long]
[--num-desc] [--out-mask=OM] [--page=PG[,SPG]]
[--quiet] [--readonly] [--six] [--transport=TN]
[--vendor=VN] [--verbose] DEVICE [DEVICE...]
sdparm [--clear=STR] [--defaults]
[--dummy] [--flexible] [--page=PG[,SPG]]
[--quiet] [--readonly] [--save] [--set=STR]
[--six] [--transport=TN] [--vendor=VN]
[--verbose] DEVICE [DEVICE...]
sdparm --command=CMD [--hex] [--long]
[--readonly] [--verbose] DEVICE [DEVICE...]
sdparm --inquiry [--all] [--examine]
[--flexible] [--hex] [--num-desc]
[--page=PG[,SPG]] [--quiet] [--readonly]
[--transport=TN] [--verbose] DEVICE
[DEVICE...]
sdparm --enumerate [--all] [--inquiry]
[--long] [--page=PG[,SPG]] [--transport=TN]
[--vendor=VN]
sdparm --inhex=FN [--all] [--flexible]
[--hex] [--inquiry] [--long] [--pdt=DT]
[--raw] [--six] [--transport=TN] [--vendor=VN]
[--verbose]
sdparm --wscan [--verbose]
sdparm [--help] [--version]
This utility fetches and potentially changes SCSI device (e.g. disk) mode pages.
Inquiry data including Vital Product Data (VPD) pages can also be displayed.
Commands associated with starting and stopping the medium; loading and
unloading the medium; and other housekeeping functions may also be issued by
this utility.
The first invocation shown in the synopsis is for accessing (i.e.
reading) mode page fields held on the DEVICE. The second form is for
changing mode page fields held on the DEVICE. The third form is for
executing some simple SCSI commands. The fourth form (i.e. the
'--inquiry ... DEVICE' form) is for fetching and decoding VPD
pages from the given DEVICE. The --enumerate form is for
listing out mode or VPD field data held by this utility (and if a
DEVICE is given then it is ignored). The --inhex=FN form
decodes mode or VPD response data provided in the named file (or from stdin
if FN=- is given); that data may either be in hexadecimal or binary.
The second last form is for Windows only and lists the available storage
device names; see the OPTIONS entry for --wscan. The final form is to
provide command line help or the version number (and date) of this
utility.
If no options (other than DEVICE) are given then a
selection of common mode page fields for that device are listed. If the
--long option is also given then a description of the fields is
placed on the right of each line. If the --all option is given then
all known mode page fields for that device are listed. Individual fields can
be displayed with the --get=STR option (e.g. '--get=WCE' to fetch the
state of the Writeback Cache Enable field).
This utility completes with an exit status of 0 when successful.
For other values see the EXIT STATUS section below.
One or more DEVICE arguments can be given. The utility will
essentially apply the given options to each DEVICE in the list. If a
error is detected, it is noted and the utility continues. Error value 5
(file open or close problem) is treated as lower priority when other errors
are detected. The exit status is the most recently detected error value
(excluding error value 5 if other errors have been detected). If all actions
succeed the exit status is zero.
By default this utility shows mode pages that are common to all
transport protocols. These are termed as "generic" mode pages. If
there is no match on a generic mode page name or field then those pages
specific to the SAS transport are checked. Transport protocol specific mode
pages are selected with the --transport=TN option. See the TRANSPORT
section below. Vendor specific mode pages are selected with the
--vendor=VN option. See the VENDORS section below.
Although originally for SCSI disks (or storage devices that appear
to the OS as SCSI disks) many of the mode pages are for other SCSI device
types. These include CD/DVD players that use the ATAPI (or any other)
transport, SCSI tapes drives and SCSI enclosures.
When the --inquiry option is given without a page number
then the Device Identification VPD page (page number 0x83) is requested and
if found it is decoded and output. If no page number is given and the
--all option is given then a list of VPD page names (but not their
contents) supported by the DEVICE is output. When both the
--inquiry and --page=PG options are given then the VPD page
can be specified as an abbreviation (e.g. "sp" for the SCSI ports
VPD page) or numerically (e.g. "0x88"). If a VPD page is returned
by the DEVICE but sdparm cannot decode it or the --hex option
is given then it is output in hex.
Mandatory arguments to long options are mandatory for short options as well. If
an option takes a numeric argument then that argument is assumed to be decimal
unless otherwise indicated (e.g. with a leading "0x" or a trailing
"h"). The options are in alphabetical order, based on the long
option name.
- -a, --all
- output all recognized fields for the device type (e.g. disk) of the
DEVICE. Without this option (or the --page=PG[,SPG] option)
the default action is to output a relatively small number of commonly used
fields from different pages. When a specific (mode) page number is given
with the --page=PG[,SPG] option then all the fields of that page
are output (irrespective of the setting of this option). For this option's
action when used with the --enumerate option see the ENUMERATE
section below.
When used together with the --inquiry option and a DEVICE, the
Supported VPD Pages VPD page [0x0] is output. When this option is used
twice (short form: '-iaa') then all VPD pages (listed in the Supported VPD
Pages VPD page) are output.
By default --inhex=FN will only decode the first mode page found in
FN. With this option, more mode pages will be decoded if present.
When --transport=TN or --vendor=VN is also given then if a
given mode page is not defined for that transport or vendor, then it is
decoded as a generic mode page.
- -c, --clear=STR
- In its simplest form STR contains a field acronym_name or a field
numerical descriptor. In the absence of an explicit value argument (e.g.
'--clear=WCE=1'), the field has its value cleared to zero. See the
PARAMETERS section below.
- -C, --command=CMD
- Perform given CMD. See section below on COMMANDS. To enumerate
supported commands use '-e -C x' (using any CMD name, valid or
otherwise).
- -B, --dbd
- disable block descriptors. This is a bit in MODE SENSE cdbs that rarely
needs to be set. One known case is a MODE SENSE 6 issued to a Reduced
Block Commands (RBC) device where the RBC standard says it shall be
set.
- -D, --defaults
- sets the given mode page to its default values. Requires the
--page=PG[,SPG] option to be given to specify the mode page. To
make the default mode page values also the saved mode page values, use the
--save option as well.
when this option is used twice, the current values in all modes pages are
reverted to their defaults. If the --save option is given as well,
then the current and saved values in all modes pages are reverted to their
defaults. This feature uses the RTD bit in the MODE SELECT command which
was added in draft SPC-5 revision 11.
- -d, --dummy
- when set inhibits changes being placed in the DEVICE's mode page.
Instead the mode data that would have been sent to a MODE SELECT command,
is output in ASCII hex to the console. This option is mainly for
testing.
- -e, --enumerate
- lists out descriptive information about the pages and fields known to this
utility. Ignores the DEVICE argument and other options apart from
the --all, --inquiry, --long, --page=PG[,SPG],
--transport=TN and --vendor=VN. If --enumerate is
given without other options then the known (generic) mode pages are
listed. See the ENUMERATE section below.
- -E, --examine
- for mode pages only those with known field names are probed when the
--all option is given. For VPD pages only those pages listed in
"Supported VPD pages page" are decoded. In both cases some pages
may be missed. With this option (i.e. --examine) all mode and VPD
pages can be probed.
For mode pages, this option will probe all mode pages from page number 0x0
to 0x3e. To probe mode subpages give a mode page number with
--page=PG and then all subpages (from 0x0 to 0xfe) are probed.
For VPD pages, use this option with --inquiry. This will cause all
VPD pages from 0x0 to 0xbf to be probed by default. A sequence of VPD
pages can be probed with --page=PG[,SPG] in which case VPD pages
from PG (lower number) to SPG (high number) inclusive are probed. Vendor
specific VPD pages run from 0xc0 to 0xff and can be probed by setting SPG
from 0xc0 to 0xff.
- -f, --flexible
- Some devices, bridges and/or drivers attempt crude transformations between
mode sense 6 and 10 byte commands without correctly rebuilding the
response. This will cause the response to be mis-interpreted (usually with
an error saying the response is malformed). With this option, the length
of the response is checked, and if it looks wrong, various corrections are
attempted. This option will also allow mode pages that don't belong to the
current device's peripheral type to be listed.
- -g, --get=STR
- In its simplest form STR contains a field acronym_name or a field
numerical descriptor. The field is fetched from mode page. See the
PARAMETERS section below. The --long and --hex options
effect the output format. Also if a value of "1" is given (e.g.
'--get=WCE=1') only the current value is output (i.e. not the change mask,
the default value and the saved value).
- -h, --help
- output the usage message then exit.
- -H, --hex
- rather than trying to decode mode (or VPD) pages, print them out in hex.
When used with the --get=STR option the corresponding current,
changeable, default and saved values are output in hex, prefixed by
"0x" and space separated. If a value of "1" is given
with the --get=STR option (e.g. '--get=WCE=1') then only the
current value is output in hex, prefixed by "0x". If a value of
"2" is given with the --get=STR option then only the
current value is output as a (signed) integer. This option can be used
multiple times (e.g. '-HH'). Useful with the ATA Information VPD page
which usually outputs its IDENTIFY (PACKET) DEVICE response in 16 bit hex
words; with '-HH' outputs that response in hex bytes; with '-HHH' outputs
the same response in a format suitable for 'hdparm --Istdin' to decode.
Mode page output with the '-HHH' option is suitable for a later invocation
of sdparm with the --inhex=FN option.
- -i, --inquiry
- output a VPD page which is in the response of a SCSI INQUIRY command sent
to DEVICE. In the absence of this option the default action is to
output mode pages. If the --inquiry option is given without the
--page=PG[,SPG] option then the device identification VPD page
(0x83) is decoded and output. If this option and the --all option
are given then the supported VPD pages page (0x0) is decoded and
output.
- -I, --inhex=FN
- FN is expected to be a file name (or '-' for stdin) which contains
ASCII hexadecimal (or binary) representing the response to MODE SENSE(10).
If --six is also given then the response from MODE SENSE(6) is
assumed. A MODE SENSE response contains a mode parameter header, then 0 or
more block descriptors followed by one or more mode pages. This utility
will only decode the first mode page unless the --all option is
given. In order to decode a mode page the peripheral device type is often
needed and can be supplied with the --pdt=DT option. If the
--pdt=DT is not given then a mode page found in two device type
standards (e.g. SBC and SSC) may be decoded twice.
If --inquiry is given then FN is interpreted as the response
data of a single VPD page.
The hexadecimal in FN should be arranged as 1 or 2 digits
representing a byte each of which is whitespace or comma separated.
Anything from and including a hash mark to the end of line is ignored. If
the --raw option is given then FN is treated as binary.
- -l, --long
- output extra information. In the case of mode page fields a description
(with units if applicable) is output to the right. If used twice, then for
some fields more information about its values is given on one or more
following lines, each prefixed by a tab character. For usage with
--enumerate see the ENUMERATE section below.
When this option is used along with --command=capacity then the READ
CAPACITY(16) is sent to the DEVICE and if successful its extended
response is output.
- -n, --num-desc
- for a mode page that can have descriptors, the number of descriptors for
the given page on the DEVICE is output. Otherwise 0 is output.
- -o, --out-mask=OM
- OM is a bit mask for mode page selections that will be
printed/output. The 0x1 value is for the 'current' values, 0x2 is for the
'changeable' values, 0x4 is for the 'default' values and 0x8 is for the
'saveable' values. The default value is 0xf (i.e. the OR of all four
values set). The option is useful for limiting the amount of output with
the '-HHH'.
- -p, --page=PG[,SPG]
- supply the page number (PG) and optionally the sub page number
(SPG) of the mode (or VPD) page to fetch. These numbers are
interpreted as decimal unless prefixed with "0x" or a trailing.
Sub page numbers are only valid for mode pages (not VPD pages).
Alternatively an abbreviation for a page can be given (see next
entry).
- -p, --page=STR
- a two or three letter abbreviation for a page can be given. Known mode
page abbreviations are checked first followed by known VPD page
abbreviations. For example '--page=ca' matches the caching mode page. If
no match is found then an error is issued and a list of possibilities in
the current context is given (so '-p x' can be quite useful). If the
STR matches a known VPD page abbreviation then the --inquiry
option is assumed. For usage with --enumerate see the ENUMERATE
section below.
- -P, --pdt=DT
- This option is only active when the --inhex=FN option is given.
DT is the peripheral Device Type, a value between 0 and 31 and can
be found in the response to the INQUIRY command. The default value is -1
(which may also be given for DT) and it is interpreted as SPC (i.e.
common mode pages) or as a wild card. If available this option should be
supplied with the --inhex=FN option.
- -q, --quiet
- suppress output of device name followed by the vendor, product and
revision strings fetched from an INQUIRY response. Without this option
such a line is typically the first line output by sdparm. Reduces output
from the device identification VPD page, typically to one line (or none)
for each of di_lu, di_port, di_target and di_asis.
If this option is used twice then additionally mode page output suppresses
the changeable, default and saved values that are usually shown in braces,
if available.
- -r, --readonly
- override other logic to open DEVICE in read-only mode. The default
setting of the open read-only/read-write mode depends on the operation
requested (e.g. a --set=STR operation by default will try a
read-write mode open on DEVICE). This option may be useful if a
command is being sent to an ATA disk via a SCSI command set. For example
in Linux '-C stop' may require this option to stop an ATA disk being
restarted immediately.
- -R, --raw
- this option is only active when used with the --inhex=FN option.
When this option is given then the file FN is interpreted as
binary; the default action (i.e. when this option is not given) is to
interpret FN as ASCII hexadecimal.
- -S, --save
- when a mode page is being modified (by using the --clear=STR and/or
--set=STR options) then the default action is to modify only the
current values mode page. When this option is given then the corresponding
value(s) in the saved values mode page is also changed. The next time the
device is power cycled (or reset) the saved values mode page becomes (i.e.
is copied to) the current values mode page. This option sets the SP field
in the MODE SELECT command. See NOTES section below.
- -s, --set=STR
- in its simplest form STR contains a field acronym_name or a field
numerical descriptor. In the absence of an explicit value, each
acronym_name has its value set to (all) ones. This means a 16 bit field
will be set to 0xffff which is 65535 in decimal. Alternatively each
acronym_name or numerical descriptor may be followed by
"=<n>" where <n> is the value to set that field to.
See the PARAMETERS section below.
- -6, --six
- The default action of this utility is to issue MODE SENSE and MODE SELECT
SCSI commands with 10 byte cdbs. When this option is given the 6 byte cdb
variants are used. RBC and old SCSI devices may need this option. This
utility outputs a suggestion to use this option if the SCSI status
indicates that the 10 byte cdb variant is not supported.
The SPC-4 standard (and SPC-5 drafts) include a note stating that
implementers migrate away from the SCSI MODE SELECT(6) and MODE SENSE(6)
commands in favour of the 10 byte variants (e.g. MODE SEMSE(10)).
- -t, --transport=TN
- Specifies the transport protocol where TN is either a number in the
range 0 to 15 (inclusive) or an abbreviation (e.g. "fcp" for the
Fibre Channel Protocol). Some transports accept multiple abbreviations,
for example srp (SCSI RDMA Protocol) and ib (short for InfiniBand) both
are accepted for transport protocol 0x4 . Also both upper and lower case
are accepted so iscsi and iSCSI are accepted for transport protocol 0x5 .
One way to list available transport protocols numbers and their associated
abbreviations is to give an invalid transport protocol name such as '-t
x'; another way is '-e -l'. N.B. The --all option may still be
needed to show all available fields.
- -M, --vendor=VN
- Specifies the vendor (i.e. manufacturer) where VN is either a
number (0 or more) or an abbreviation (e.g. "sea" for Seagate
disk vendor specific). For tape drives "lto5" and
"lto6" are treated as vendors. One way to list the available
vendor numbers and their associated abbreviations is to give an invalid
vendor number such as '-M x'; another way is '-e -l'.
This option only effects mode page decodes, not VPD pages. For vendor
specific VPD pages see the sg_vpd utility.
- -v, --verbose
- increase the level of verbosity, (i.e. debug output). In some cases more
decoding is done (e.g. fields within a standard INQUIRY response).
- -V, --version
- print the version string and then exit.
- -w, --wscan
- this option is available in Windows only. It lists storage device names
and the corresponding volumes, if any. When used twice it adds the
"bus type" of the closest transport (e.g. a SATA disk in a USB
connected enclosure has bus type Usb). When used three times a SCSI
adapter scan is added. When used four times only a SCSI adapter scan is
shown. See examples below and the "Win32 port" section in the
README file.
The reference document used for interpreting mode and VPD pages (and the INQUIRY
standard response) is T10/BSR INCITS 502 Revision 17 (SPC-5, 19 September
2017) found at http://www.t10.org . Obsolete and reserved items in the
standard INQUIRY response output are displayed in brackets. Recent drafts of
other T10 documents are also used: SBC-4 (disks), SSC-5 (tapes), SPL-5 (SAS
transport) and SAT-4 (SCSI to ATA Translation).
A mode page for which no abbreviation is known (e.g. a vendor
specific mode page) can be listed in hexadecimal by using the option
combination '--page=PG --hex'.
Numbers input to sdparm (e.g. in the command line arguments) are
assumed to be in decimal unless there is a hexadecimal indicator. A
hexadecimal indicator is either a leading '0x' or '0X' (i.e. the C language
convention) or a trailing 'h' or 'H' (i.e. the convention used at
www.t10.org ). In the case of --page= either a string or number is
expected, so hex numbers like 'ch' (12) should be prefixed by a zero (e.g.
'0ch').
The SPC-4 draft (rev 2) says that devices that implement no
distinction between current and saved pages can return an error (ILLEGAL
REQUEST, invalid field in cdb) if the SP bit (which corresponds to the
--save option) is _not_ set. In such cases the --save option
needs to be given.
If the --save option is given but the existing mode page
indicates (via its PS bit) that the page is not saveable, then this utility
generates an error message. That message suggests to try again without the
--save option.
Since the device identification VPD page (acronym_name
"di") potentially contains a lot of diverse designators, several
associated acronyms are available. They are "di_lu" for
designators associated with the addressed logical unit, "di_port"
for designators associated with the target port (which the command arrived
via) and "di_target" for designators associated with the target
device. When "di" is used designators are grouped by lu, then port
and then target device. To see all designators decoded in the order that
they appear in the VPD page use "di_asis".
Only those VPD pages defined by t10.org are decoded by this
utility. SPC-4 sets aside VPD pages codes from 0xc0 to 0xff (inclusive) for
vendor specific pages some of which are decoded in the sg_vpd utility.
To see all VPD pages supported by a DEVICE use 'sg_vpd
--all'.
In the linux kernel 2.6 and 3 series any device node that
understands a SCSI command set (e.g. SCSI disks and CD/DVD drives) may be
specified. More precisely the driver that "owns" the device node
must support the SG_IO ioctl. In the lk 2.4 series only SCSI generic (sg)
device nodes support the SG_IO ioctl. However in the lk 2.4 series other
SCSI device nodes are mapped within this utility to their corresponding sg
device nodes. So if there is a SCSI disk at /dev/sda then 'sdparm /dev/sda'
will work in both the lk 2.4 series and later. However if there is an ATAPI
cd/dvd drive at /dev/hdc then 'sdparm /dev/hdc' will only work in the lk 2.6
series and later.
In the Linux 2.6 and 3 series, especially with ATA disks, using
sdparm to stop (spin down) a disk may not be sufficient and other mechanisms
will start the disk again some time later. The user might additionally mark
the disk as "offline" with 'echo offline >
/sys/block/sda/device/state' where sda is the block name of the disk. To
restart the disk "offline" can be replaced with
"running".
In their simplest form the --clear=, --get= and --set=
options (or their short forms) take an acronym_name such as "WCE".
In the case of '--get=WCE' the value of "Writeback Cache Enable" in
the caching mode page will be fetched. In the case of '--set=WCE' that bit
will be set (to one). In the case of '--clear=WCE' that bit will be cleared
(to zero). When an acronym_name is given then the mode page is imputed from
that acronym_name (e.g. WCE is in the caching mode page).
Instead of an acronym_name a field within a mode page can be
described numerically with a
<start_byte>:<start_bit>:<num_bits> tuple. These are the
<start_byte> (origin 0) within the mode page, a <start_bit> (0
to 7 inclusive) and <num_bits> (1 to 64 inclusive). For example, the
low level representation of the RCD bit (the "Read Cache Disable bit in
the caching mode page) is "2:0:1". The <start_byte> can
optionally be given in hex (e.g. '--set=0x2:0:1' or '--set=2h:0:1'). With
this form the --page= option is required to establish which mode page
is to be used.
Either form can optionally be followed by
"=<val>". By default <val> is decimal but can be given
in hex in the normal fashion. Here are some examples: '--set=2h:0:1=1h' and
'-s MRIE=0x3'. When the acronym_name or numeric form following
--clear= is not given an explicit '=<val>' then the value
defaults to zero. When the acronym_name or numeric form following
--set= is not given an explicit '=<val>' then the value
defaults to "all ones" (i.e. as many as <num_bits> permits).
For example '--clear=WCE' and '--clear=WCE=0' have the same meaning: clear
Writeback Cache Enable or, put more simply: turn off the writeback
cache.
Multiple fields within the same mode page can be changed by giving
a comma separated list of acronym_names and/or the numerical form. For
example: '--set=TEST,MRIE=6'.
Some mode page have multiple descriptors. They typically have a
fixed header section at the start of the mode page that includes a field
containing the number of descriptors that follow. Following the header is a
variable number of descriptors. An example is the SAS Phy Control and
Discover mode page. An acronym_name may include a trailing '.<num>'
where "<num>" is a descriptor number (origin 0). For example
'-t sas -g PHID.0' and '-t sas -g PHID' will yield the phy identifier of the
first descriptor of the above mode page; '-t sas -g PHID.1' will yield the
phy identifier of the second descriptor.
The --enumerate option essentially dumps out static information held by
this utility. A list of --enumerate variants and their actions follows.
For brevity subsequent examples of options are shown in their shorter form.
--enumerate list generic mode page information
-e --all list generic mode page contents
(i.e. parameters)
-e --page=rw list contents of read write error
recovery mode page
-e --inquiry list VPD pages this utility can decode
-e --long list generic mode pages, transport
protocols, mode pages for each
supported transport protocol and
supported commands
-e -l --all additionally list the contents of
each mode page
-e --transport=fcp list mode pages for the fcp
transport protocol
-e -t fcp --all additionally list the contents of
each mode page
-e --vendor=sea list vendor specific mode pages for
"sea" (Seagate)
-e -M sea --all additionally list the contents of vendor
specific mode pages for "sea" (Seagate)
-e -p pcd -l list contents of SAS phy control and
discovery mode page plus (due to "-l")
some descfriptor format information
When known mode pages are listed (via the --enumerate
option) each line starts with a two or three letter abbreviation. This is
followed by the page number (in hex prefixed by "0x") optionally
followed by a comma and the subpage number. Finally the descriptive name of
the mode page (e.g. as found in SPC-4) is output.
When known parameters (fields) of a mode page are listed, each
line starts with an acronym (indented a few spaces). This will match (or be
an acronym for) the description for that field found in the (draft)
standards. Next are three numbers, separated by colons, surrounded by
brackets. These are the start byte (in hex, prefixed by "0x") of
the beginning of the field within the mode page; the starting bit (0 through
7 inclusive) and then the number of bits. The descriptive name of the
parameter (field) is then given. If appropriate the descriptive name
includes units (e.g. "(ms)" means the units are milliseconds).
Adding the '-ll' option will list information about possible field values
for selected mode page parameters.
Mode parameters for which the num_bits is greater than 1 can be
viewed as unsigned integers. Often 16 and 32 bit fields are set to 0xffff
and 0xffffffff respectively (all ones) which usually has a special meaning
(see drafts). This utility outputs such values as "-1" to save
space (rather than their unsigned integer equivalents). "-1" can
also be given as the value to a mode page field acronym (e.g.
'--set=INTT=-1' sets the interval timer field in the Informational
Exceptions control mode page to 0xffffffff).
SCSI transport protocols are a relatively specialized area that can be safely
ignored by the majority of users.
Some transport protocols have protocol specific mode pages. These
are usually the disconnect-reconnect (0x2), the protocol specific logical
unit (0x18) and the protocol specific port (0x19) mode pages. In some cases
the latter mode page has several subpages. The most common transport
protocol abbreviations likely to be used are "fcp",
"spi" and "sas".
Many of the field names are re-used in the same position so the
acronym_name namespaces have been divided between generic mode pages (i.e.
when the --transport= option is _not_ given) and a namespace for each
transport protocol. A LUPID field from the protocol specific logical unit
(0x18) mode page and the PPID field from protocol specific port (0x19) mode
page are included in the generic modes pages; this is so the respective
(transport) protocol identifiers can be seen. In most cases the user will
know what the "port" transport is (i.e. the same transport as the
HBA in the computer) but the logical unit's transport could be
different.
SCSI leaves a lot of space for vendor specific information. Often this is
described in product manuals. The --vendor=VN (or -M=VN) option
allows known vendor specific mode pages to be examined and/or modified by
acronym.
In this utility the syntax and semantics of vendor specific mode
pages is very similar to those of transport protocol specific mode pages.
Both cannot be specified together. Vendor specific modes pages can still be
accessed numerically (as shown at the end of the EXAMPLES section).
The command option sends a SCSI command to the DEVICE. If the command
fails then this is reflected in the non-zero exit status. To obtain more
information about the error use the -v option.
- capacity
- sends a READ CAPACITY(10) command (valid for disks and cd/dvd media) by
default. If successful yields "blocks: " [the number of blocks],
"block_length: " [typically either 512 or 2048] and
"capacity_mib: " [capacity in MibiBytes (1048576 byte
units)].
If the number of blocks is too large to fit in the 4 byte field
provided by READ CAPACITY(10) or, the --long option is given, then
the READ CAPACITY(16) command is sent. If the --long option is given,
then the extra fields found in the READ CAPACITY(16) response are
output.
- eject
- stops the medium and ejects it from the device. Note that ejection (by
command or button) may be prevented in which case the 'unlock' command may
be useful in extreme cases. Typically only appropriate for cd/dvd drives
and disk drives with removable media. Objects if sent to another
peripheral device type (but objection can be overridden with '-f'
option).
- load
- loads the medium and starts it (i.e. spins it up). See 'eject' command for
supported device types.
- profile
- lists the various formats that a CD/DVD/HD-DVD/BD drive supports. These
are called "profiles" in the MMC standard. The profiles are
listed one per line. If media is in the drive then the profile that
matches the media (if any) has an "*" to the right of the
line.
- ready
- sends the "Test Unit Ready" SCSI command to the DEVICE.
No error is reported if the device will respond to data requests (e.g.
READ) in a reasonable timescale. For example, if a disk is stopped then it
will report "not ready". All devices should respond to this
command.
- sense
- sends a REQUEST SENSE command. It reports a hardware threshold exceeded,
warning or low power condition if flagged. If a progress indication is
present (e.g. during a format) then it will be output as a percentage.
Yields a process status of 0 if the command succeeds and the sense key is
0; else yields 1. The --quiet option can be used to lessen output,
and --hex to output sense data in hex.
- speed=SPEED
- permits the speed of a CD, DVD, HD_DVD or BD disc in a drive to be set (or
at least influenced). It has this format: --command=speed=SPEED
where SPEED is in kilobytes per second. In this case a kilobyte is 1000
bytes. The "times one" speed for a CD is 176.4 kB/s, for a DVD
is 1350 kB/s and for both HD-DVD and BD it is 4500 kB/s. If SPEED is zero
then the drive is set to the speed that it considers gives optimal
performance. This command sends a SET STREAMING multi-media command (MMC)
to the drive. The EXACT bit is clear so the drive will round the given
SPEED as necessary. The command is designed to control read speed; setting
write speed should be left to "burning" programs.
- start
- starts the medium (i.e. spins it up). Harmless if medium has already been
started. See 'eject' command for supported device types. If the
DEVICE is an ATA disk in Linux the '--readonly' option may be
required.
- stop
- stops the medium (i.e. spins it down). Harmless if medium has already been
stopped. See 'eject' command for supported device types. If the
DEVICE is an ATA disk in Linux the '--readonly' option may be
required. See the NOTES section above.
- sync
- sends a SYNCHRONIZE CACHE command. The device should flush any data held
in its (volatile) buffers to the media.
- unlock
- tells a device to allow medium removal. It uses the SCSI "prevent
allow medium removal" command. This is desperation stuff, possibly
overriding a prevention applied by the OS on a mounted file system. The
"eject" utility (from the "eject" package) is more
graceful and should be tried first. This command is only appropriate for
devices with removable media.
For loading and ejecting tapes the mt utility should be used (i.e.
not these commands). The 'ready' command is valid for tape devices.
To list the common (generic) mode parameters of a disk:
sdparm /dev/sda
To list the designators within the device identification VPD page
of a disk:
sdparm --inquiry /dev/sda
To see all parameters for the caching mode page:
sdparm --page=ca /dev/sda
To see all parameters for the caching mode page with parameter
descriptions to the right:
sdparm --page=ca --long /dev/sda
To get the WCE values (current changeable default and saved) in
hex:
sdparm -g WCE -H /dev/sda
0x01 0x00 0x01 0x01
To get the WCE current value in hex:
sdparm -g WCE=1 -H /dev/sda
0x01
To set the "Writeback Cache Enable" bit in the current
values page:
sdparm --set=WCE /dev/sda
To set the "Writeback Cache Enable" bit in the current
and saved values page:
sdparm --set=WCE --save /dev/sda
To set the "Writeback Cache Enable" and clear "Read
Cache Disable":
sdparm --set=WCE --clear=RCD --save /dev/sda
The previous example can also by written as:
sdparm -s WCE=1,RCD=0 -S /dev/sda
To re-establish the manufacturer's defaults in the current and
saved values of the caching mode page:
sdparm --page=ca --defaults --save /dev/sda
If an ATAPI cd/dvd drive is at /dev/hdc then its common (mode)
parameters could be listed in the lk 2.6 and 3 series with:
sdparm /dev/hdc
If there is a DVD in the drive at /dev/hdc then it could be
ejected in the lk 2.6 and 3 series with:
sdparm --command=eject /dev/hdc
If the ejection is being prevented by software then that can be
overridden with:
sdparm --command=unlock /dev/hdc
One disk vendor has a "Performance Mode" bit (PM) in the
vendor specific unit attention mode page [0x0,0x0]. PM=0 is server mode (the
default) while PM=1 is desktop mode. Desktop mode can be set (both current
and saved values) with:
sdparm --page=0 --set=2:7:1=1 --save /dev/sda
The resultant change can be viewed in hex with the --hex
option as there are no acronyms for vendor extensions yet. The PM bit is now
covered by vendor specific mode pages and the above can also be accomplished
with:
sdparm --vendor=sea --set=PM --save /dev/sda
What follows are some examples from Windows using the '--wscan'
option. The idea is to list the storage device names on the system that
might be invoked by other uses of sdparm.
# sdparm --wscan
PD0 [C] FUJITSU MHY2160BH 0000
PD1 [DF] WD 2500BEV External 1.05 WD-WXE90
CDROM0 [E] MATSHITA DVD/CDRW UJDA775 CB03
So 'sdparm -a CDROM0' and 'sdparm -a E' will show all the (known)
mode page fields for the Matshita DVD/CD drive. By using the '--wscan'
option twice, the bus type (as seen by the OS) is added to the output:
# sdparm -ww
PD0 [C] <Ata > FUJITSU MHY2160BH 0000
PD1 [DF] <Usb > WD 2500BEV External 1.05 WD-WXE90
CDROM0 [E] <Atapi> MATSHITA DVD/CDRW UJDA775 CB03
And the pattern continues to add a SCSI adapter scan. This may be
useful if there are specialized storage related devices (e.g. a SES device
in an enclosure) but does add much extra information in this case.
# sdparm -www
PD0 [C] <Ata > FUJITSU MHY2160BH 0000
PD1 [DF] <Usb > WD 2500BEV External 1.05 WD-WXE90
CDROM0 [E] <Atapi> MATSHITA DVD/CDRW UJDA775 CB03
SCSI0:0,0,0 claimed=1 pdt=0h FUJITSU MHY2160BH 0000
SCSI1:0,0,0 claimed=1 pdt=5h MATSHITA DVD/CDRW UJDA775 CB03
To aid scripts that call sdparm, the exit status is set to indicate success (0)
or failure (1 or more). Note that some of the lower values correspond to the
SCSI sense key values. The exit status values are:
- 0
- success
- 1
- syntax error. Either illegal command line options, options with bad
arguments or a combination of options that is not permitted.
- 2
- the DEVICE reports that it is not ready for the operation
requested. The device may be in the process of becoming ready (e.g.
spinning up but not at speed) so the utility may work after a wait.
- 3
- the DEVICE reports a medium or hardware error (or a blank check).
For example an attempt to read a corrupted block on a disk will yield this
value.
- 5
- the DEVICE reports an "illegal request" with an
additional sense code other than "invalid operation code". This
is often a supported command with a field set requesting an unsupported
capability. For commands that require a "service action" field
this value can indicate that the command is not supported.
- 6
- the DEVICE reports a "unit attention" condition. This
usually indicates that something unrelated to the requested command has
occurred (e.g. a device reset) potentially before the current SCSI command
was sent. The requested command has not been executed by the device. Note
that unit attention conditions are usually only reported once by a
device.
- 7
- the DEVICE reports a "data protect" sense key. This
implies some mechanism has blocked writes (or possibly all access to the
media).
- 9
- the DEVICE reports an illegal request with an additional sense code
of "invalid operation code" which means that it doesn't support
the requested command.
- 10
- the DEVICE reports a "copy aborted". This implies another
command or device problem has stopped a copy operation. The EXTENDED COPY
family of commands (including WRITE USING TOKEN) may return this sense
key.
- 11
- the DEVICE reports an aborted command. In some cases aborted
commands can be retried immediately (e.g. if the transport aborted the
command due to congestion).
- 14
- the DEVICE reports a miscompare sense key. VERIFY and COMPARE AND
WRITE commands may report this.
- 15
- the utility is unable to open, close or use the given DEVICE. The
given file name could be incorrect or there may be permission problems.
Adding the -v option may give more information.
- 20
- the DEVICE reports it has a check condition but "no
sense". Some polling commands (e.g. REQUEST SENSE) can react this
way. It is unlikely that this value will occur as an exit status.
- 21
- the DEVICE reports a "recovered error". The requested
command was successful. Most likely a utility will report a recovered
error to stderr and continue, probably leaving the utility with an exit
status of 0 .
- 22
- the DEVICE reports that the current command or its parameters imply
a logical block address (LBA) that is out of range.
- 24
- the DEVICE reports a SCSI status of "reservation
conflict". This means access to the DEVICE with the current
command has been blocked because another machine (HBA or SCSI
"initiator") holds a reservation on this DEVICE. On
modern SCSI systems this is related to the use of the PERSISTENT
RESERVATION family of commands.
- 25
- the DEVICE reports a SCSI status of "condition met".
Currently only the PRE-FETCH command (see SBC-4) yields this status.
- 26
- the DEVICE reports a SCSI status of "busy". SAM-5 defines
this status as the logical unit is temporarily unable to process a
command. It is recommended to re-issue the command.
- 27
- the DEVICE reports a SCSI status of "task set full".
- 28
- the DEVICE reports a SCSI status of "ACA active". ACA is
"auto contingent allegiance" and is seldom used.
- 29
- the DEVICE reports a SCSI status of "task aborted". SAM-5
says: "This status shall be returned if a command is aborted by a
command or task management function on another I_T nexus and the Control
mode page TAS bit is set to one".
- 33
- the command sent to DEVICE has timed out. This occurs in Linux
only; in other ports a command timeout will appear as a transport (or OS)
error.
- 40
- the command sent to DEVICE has received an "aborted
command" sense key with an additional sense code of 0x10. This value
is related to problems with protection information (PI or DIF). For
example this error may occur when reading a block on a drive that has
never been written (or is unmapped) if that drive was formatted with type
1, 2 or 3 protection.
- 48
- this is an internal message indicating a NVMe status field (SF) is other
than zero after a command has been executed (i.e. something went wrong).
Work in this area is currently experimental.
- 49
- low level driver reports a response's residual count (i.e. number of bytes
actually received by HBA is 'requested_bytes - residual_count') that is
too high. So no useful processing can be done with that response.
- 50 + <os_error_number>
- OS system calls that fail often return a small integer number to help
indicate what the error is. For example in Unix the inability of a system
call to allocate memory returns (in 'errno') ENOMEM which often is
associated with the integer 12. So 62 (i.e. '50 + 12') may be returned by
a utility in this case.
- 97
- the response to a SCSI command failed sanity checks.
- 98
- the DEVICE reports it has a check condition but the error doesn't
fit into any of the above categories.
- 99
- any errors that can't be categorized into values 1 to 98 may yield this
value. This includes transport and operating system errors after the
command has been sent to the device.
- 126
- the utility was found but could not be executed. That might occur if the
executable does not have execute permissions.
- 127
- This is the exit status for utility not found. That might occur when a
script calls a utility in this package but the PATH environment variable
has not been properly set up, so the script cannot find the
executable.
- 128 + <signum>
- If a signal kills a utility then the exit status is 128 plus the signal
number. For example if a segmentation fault occurs then a utility is
typically killed by SIGSEGV which according to 'man 7 signal' has an
associated signal number of 11; so the exit status will be 139 .
- 255
- the utility tried to yield an exit status of 255 or larger. That should
not happen; given here for completeness.
Most of the error conditions reported above will be repeatable (an
example of one that is not is "unit attention") so the utility can
be run again with the -v option (or several) to obtain more
information.
Written by Douglas Gilbert.
Report bugs to <dgilbert at interlog dot com>.
Copyright © 2005-2021 Douglas Gilbert
This software is distributed under a FreeBSD license. There is NO warranty; not
even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
There is a web page discussing this package at
https://sg.danny.cz/sg/sdparm.html .
hdparm(hdparm), sg_modes, sg_wr_mode, sginfo, sg_inq, sg_vpd(all in
sg3_utils), smartmontools(smartmontools.sourceforge.net), mt,
eject(eject),