smartctl [options] device
smartmontools-5.41 2011-06-09 r3365
smartctl controls the Self-Monitoring, Analysis and Reporting Technol-
ogy (SMART) system built into many ATA-3 and later ATA, IDE and SCSI-3
hard drives. The purpose of SMART is to monitor the reliability of the
hard drive and predict drive failures, and to carry out different types
of drive self-tests. This version of smartctl is compatible with
ATA/ATAPI-7 and earlier standards (see REFERENCES below)
smartctl is a command line utility designed to perform SMART tasks such
as printing the SMART self-test and error logs, enabling and disabling
SMART automatic testing, and initiating device self-tests. Note: if the
user issues a SMART command that is (apparently) not implemented by the
device, smartctl will print a warning message but issue the command
anyway (see the -T, --tolerance option below). This should not cause
problems: on most devices, unimplemented SMART commands issued to a
drive are ignored and/or return an error.
smartctl also provides support for polling TapeAlert messages from SCSI
tape drives and changers.
The user must specify the device to be controlled or interrogated as
the final argument to smartctl. The command set used by the device is
often derived from the device path but may need help with the '-d'
option (for more information see the section on "ATA, SCSI command sets
and SAT" below). Device paths are as follows:
LINUX: Use the forms "/dev/hd[a-t]" for IDE/ATA devices, and
"/dev/sd[a-z]" for SCSI devices. For SCSI Tape Drives and
Changers with TapeAlert support use the devices "/dev/nst*"
and "/dev/sg*". For SATA disks accessed with libata, use
"/dev/sd[a-z]" and append "-d ata". For disks behind 3ware
controllers you may need "/dev/sd[a-z]" or "/dev/twe[0-9]",
"/dev/twa[0-9]" or "/dev/twl[0-9]": see details below. For
disks behind HighPoint RocketRAID controllers you may need
"/dev/sd[a-z]". For disks behind Areca SATA RAID controllers,
you need "/dev/sg[2-9]" (note that smartmontools interacts
with the Areca controllers via a SCSI generic device which is
different than the SCSI device used for reading and writing
and "/dev/st[0-9]+c" respectively. Be sure to specify the
correct "whole disk" partition letter for your architecture.
SOLARIS: Use the forms "/dev/rdsk/c?t?d?s?" for IDE/ATA and SCSI disk
devices, and "/dev/rmt/*" for SCSI tape devices.
Use the forms "/dev/hd[a-d]" for standard IDE/ATA devices
accessed via SMARTVSD.VXD, and "/dev/hd[e-h]" for additional
devices accessed via a patched SMARTVSE.VXD (see INSTALL file
for details). Use the form "/dev/scsi[0-9][0-f]" for SCSI
devices via an aspi dll on ASPI adapter 0-9, ID 0-15. The pre-
fix "/dev/" is optional.
Use the forms "/dev/sd[a-z]" for IDE/(S)ATA and SCSI disks
"\\.\PhysicalDrive[0-25]" (where "a" maps to "0"). These
disks can also be referred to as "/dev/pd[0-255]" for
"\\.\PhysicalDrive[0-255]". ATA disks can also be referred to
as "/dev/hd[a-z]" for "\\.\PhysicalDrive[0-25]". Use one the
forms "/dev/tape[0-255]", "/dev/st[0-255]", or
"/dev/nst[0-255]" for SCSI tape drives "\\.\Tape[0-255]".
Alternatively, drive letters "X:" or "X:\" may be used to
specify the ('basic') disk behind a mounted partition. This
does not work with 'dynamic' disks.
For disks behind 3ware 9000 controllers use "/dev/sd[a-z],N"
where N specifies the disk number (3ware 'port') behind the
controller providing the logical drive ('unit') specified by
"/dev/sd[a-z]". Alternatively, use "/dev/tw_cli/cx/py" for
controller x, port y to run the 'tw_cli' tool and parse the
output. This provides limited monitoring ('-i', '-c', '-A'
below) if SMART support is missing in the driver. Use
"/dev/tw_cli/stdin" or "/dev/tw_cli/clip" to parse CLI or 3DM
output from standard input or clipboard. The option '-d
3ware,N' is not necessary on Windows.
[NEW EXPERIMENTAL SMARTCTL FEATURE] For disks behind Intel
Matrix RAID driver use "/dev/csmi[0-9],N" where N specifies
the port behind the logical scsi controller "\\.\Scsi[0-9]:".
The prefix "/dev/" is optional.
CYGWIN: See "WINDOWS NT4/2000/XP/2003/Vista/Win7/2008" above.
Use the form "/dev/hd[a-z]" for IDE/ATA devices.
if '-' is specified as the device path, smartctl reads and interprets
it's own debug output from standard input. See '-r ataioctl' below for
Based on the device path, smartctl will guess the device type (ATA or
SCSI). If necessary, the '-d' option can be used to over-ride this
ENABLE/DISABLE, DISPLAY DATA, RUN/ABORT TESTS.
SHOW INFORMATION OPTIONS:
-h, --help, --usage
Prints a usage message to STDOUT and exits.
-V, --version, --copyright, --license
Prints version, copyright, license, home page and SVN revision
information for your copy of smartctl to STDOUT and then exits.
Please include this information if you are reporting bugs or
Prints the device model number, serial number, firmware version,
and ATA Standard version/revision information. Says if the
device supports SMART, and if so, whether SMART support is cur-
rently enabled or disabled. If the device supports Logical
Block Address mode (LBA mode) print current user drive capacity
in bytes. (If drive is has a user protected area reserved, or is
"clipped", this may be smaller than the potential maximum drive
capacity.) Indicates if the drive is in the smartmontools data-
base (see '-v' options below). If so, the drive model family
may also be printed. If '-n' (see below) is specified, the power
mode of the drive is printed.
Prints all SMART information about the disk, or TapeAlert infor-
mation about the tape drive or changer. For ATA devices this is
'-H -i -c -A -l error -l selftest -l selective'
and for SCSI, this is equivalent to
'-H -i -A -l error -l selftest'.
Note that for ATA disks this does not enable the non-SMART
options and the SMART options which require support for 48-bit
Prints all SMART and non-SMART information about the device. For
ATA devices this is equivalent to
'-H -i -c -A -f brief -l xerror,error -l xselftest,selftest
-l selective -l directory -l scttemp -l scterc -l sataphy'.
and for SCSI, this is equivalent to
'-H -i -A -l error -l selftest -l background -l sasphy'.
--scan Scans for devices and prints each device name, device type and
protocol ([ATA] or [SCSI]) info. May be used in conjunction
with '-d TYPE' to restrict the scan to a specific TYPE. See
also info about platform specific device scan and the DEVICESCAN
directive on smartd(8) man page.
Same as --scan, but also tries to open each device before print-
Specifies that smartctl should run in one of the two quiet modes
described here. The valid arguments to this option are:
errorsonly - only print: For the '-l error' option, if nonzero,
the number of errors recorded in the SMART error log and the
power-on time when they occurred; For the '-l selftest' option,
errors recorded in the device self-test log; For the '-H'
option, SMART "disk failing" status or device Attributes
(pre-failure or usage) which failed either now or in the past;
For the '-A' option, device Attributes (pre-failure or usage)
which failed either now or in the past.
silent - print no output. The only way to learn about what was
found is to use the exit status of smartctl (see RETURN VALUES
noserial - Do not print the serial number of the device.
-d TYPE, --device=TYPE
Specifies the type of the device. The valid arguments to this
auto - attempt to guess the device type from the device name or
from controller type info provided by the operating system or
from a matching USB ID entry in the drive database. This is the
test - prints the guessed type, then opens the device and prints
the (possibly changed) TYPE name and then exists without per-
forming any further commands.
ata - the device type is ATA. This prevents smartctl from issu-
ing SCSI commands to an ATA device.
scsi - the device type is SCSI. This prevents smartctl from
issuing ATA commands to a SCSI device.
sat - the device type is SCSI to ATA Translation (SAT). This is
for ATA disks that have a SCSI to ATA Translation (SAT) Layer
(SATL) between the disk and the operating system. SAT defines
two ATA PASS THROUGH SCSI commands, one 12 bytes long and the
other 16 bytes long. The default is the 16 byte variant which
can be overridden with either '-d sat,12' or '-d sat,16'.
usbcypress - this device type is for ATA disks that are behind a
Cypress USB to PATA bridge. This will use the ATACB proprietary
scsi pass through command. The default SCSI operation code is
0x24, but although it can be overridden with '-d usbcy-
press,0xN', where N is the scsi operation code, you're running
the risk of damage to the device or filesystems on it.
usbjmicron - this device type is for SATA disks that are behind
a JMicron USB to PATA/SATA bridge. The 48-bit ATA commands
(required e.g. for '-l xerror', see below) do not work with all
usbsunplus - this device type is for SATA disks that are behind
a SunplusIT USB to SATA bridge.
marvell - [Linux only] interact with SATA disks behind Marvell
chip-set controllers (using the Marvell rather than libata
megaraid,N - [Linux only] the device consists of one or more
SCSI/SAS disks connected to a MegaRAID controller. The non-neg-
ative integer N (in the range of 0 to 127 inclusive) denotes
which disk on the controller is monitored. Use syntax such as:
smartctl -a -d megaraid,2 /dev/sda
smartctl -a -d megaraid,0 /dev/sdb
This interface will also work for Dell PERC controllers. The
following /dev/XXX entry must exist:
For PERC2/3/4 controllers: /dev/megadev0
For PERC5/6 controllers: /dev/megaraid_sas_ioctl_node
3ware,N - [FreeBSD and Linux only] the device consists of one or
more ATA disks connected to a 3ware RAID controller. The non-
negative integer N (in the range from 0 to 127 inclusive)
denotes which disk on the controller is monitored. Use syntax
smartctl -a -d 3ware,2 /dev/sda
smartctl -a -d 3ware,0 /dev/twe0
smartctl -a -d 3ware,1 /dev/twa0
smartctl -a -d 3ware,1 /dev/twl0
The first two forms, which refer to devices /dev/sda-z and
/dev/twe0-15, may be used with 3ware series 6000, 7000, and 8000
series controllers that use the 3x-xxxx driver. Note that the
/dev/sda-z form is deprecated starting with the Linux 2.6 kernel
series and may not be supported by the Linux kernel in the near
future. The final form, which refers to devices /dev/twa0-15,
must be used with 3ware 9000 series controllers, which use the
The devices /dev/twl0-15 must be used with the 3ware/LSI 9750
series controllers which use the 3w-sas driver.
Note that if the special character device nodes /dev/twl?,
/dev/twa? and /dev/twe? do not exist, or exist with the incor-
rect major or minor numbers, smartctl will recreate them on the
fly. Typically /dev/twa0 refers to the first 9000-series con-
troller, /dev/twa1 refers to the second 9000 series controller,
and so on. The /dev/twl0 devices refers to the first 9750
series controller, /dev/twl1 resfers to the second 9750 series
controller, and so on. Likewise /dev/twe0 refers to the first
6/7/8000-series controller, /dev/twe1 refers to the second
6/7/8000 series controller, and so on.
Note that for the 6/7/8000 controllers, any of the physical
disks can be queried or examined using any of the 3ware's SCSI
logical device /dev/sd? entries. Thus, if logical device
/dev/sda is made up of two physical disks (3ware ports zero and
a disk attached to it, the behavior of smartctl depends upon the
specific controller model, firmware, Linux kernel and platform.
In some cases you will get a warning message that the device
does not exist. In other cases you will be presented with
'void' data for a non-existent device.
Note that if the /dev/sd? addressing form is used, then older
3w-xxxx drivers do not pass the "Enable Autosave" ('-S on') and
"Enable Automatic Offline" ('-o on') commands to the disk, and
produce these types of harmless syslog error messages instead:
"3w-xxxx: tw_ioctl(): Passthru size (123392) too big". This can
be fixed by upgrading to version 1.02.00.037 or later of the
3w-xxxx driver, or by applying a patch to older versions.
Alternatively, use the character device /dev/twe0-15 interface.
The selective self-test functions ('-t select,A-B') are only
supported using the character device interface /dev/twl0-15,
/dev/twa0-15 and /dev/twe0-15. The necessary WRITE LOG commands
can not be passed through the SCSI interface.
areca,N - [Linux only] the device consists of one or more SATA
disks connected to an Areca SATA RAID controller. The positive
integer N (in the range from 1 to 24 inclusive) denotes which
disk on the controller is monitored. Use syntax such as:
smartctl -a -d areca,2 /dev/sg2
smartctl -a -d areca,3 /dev/sg3
The first line above addresses the second disk on the first
Areca RAID controller. The second line addresses the third disk
on the second Areca RAID controller. To help identify the cor-
rect device, use the command:
cat /proc/scsi/sg/device_hdr /proc/scsi/sg/devices
to show the SCSI generic devices (one per line, starting with
/dev/sg0). The correct SCSI generic devices to address for
smartmontools are the ones with the type field equal to 3. If
the incorrect device is addressed, please read the warning/error
messages carefully. They should provide hints about what
devices to use.
Important: the Areca controller must have firmware version 1.46
or later. Lower-numbered firmware versions will give (harmless)
SCSI error messages and no SMART information.
cciss,N - [FreeBSD and Linux only] the device consists of one or
more SCSI/SAS disks connected to a cciss RAID controller. The
non-negative integer N (in the range from 0 to 15 inclusive)
denotes which disk on the controller is monitored.
If the controller firmware or driver provides a SAT Layer it may
be possible to monitor also SATA disks by specifiying '-d
hpt,L/M/N - [FreeBSD and Linux only] the device consists of one
or more ATA disks connected to a HighPoint RocketRAID con-
troller. The integer L is the controller id, the integer M is
device which the driver registered (eg, /dev/hptrr,
-T TYPE, --tolerance=TYPE
[ATA only] Specifies how tolerant smartctl should be of ATA and
SMART command failures.
The behavior of smartctl depends upon whether the command is
"optional" or "mandatory". Here "mandatory" means "required by
the ATA/ATAPI-5 Specification if the device implements the SMART
command set" and "optional" means "not required by the
ATA/ATAPI-5 Specification even if the device implements the
SMART command set." The "mandatory" ATA and SMART commands are:
(1) ATA IDENTIFY DEVICE, (2) SMART ENABLE/DISABLE ATTRIBUTE
AUTOSAVE, (3) SMART ENABLE/DISABLE, and (4) SMART RETURN STATUS.
The valid arguments to this option are:
normal - exit on failure of any mandatory SMART command, and
ignore all failures of optional SMART commands. This is the
default. Note that on some devices, issuing unimplemented
optional SMART commands doesn't cause an error. This can result
in misleading smartctl messages such as "Feature X not imple-
mented", followed shortly by "Feature X: enabled". In most such
cases, contrary to the final message, Feature X is not enabled.
conservative - exit on failure of any optional SMART command.
permissive - ignore failure(s) of mandatory SMART commands.
This option may be given more than once. Each additional use of
this option will cause one more additional failure to be
ignored. Note that the use of this option can lead to messages
like "Feature X not implemented", followed shortly by "Error:
unable to enable Feature X". In a few such cases, contrary to
the final message, Feature X is enabled.
verypermissive - equivalent to giving a large number of '-T per-
missive' options: ignore failures of any number of mandatory
SMART commands. Please see the note above.
-b TYPE, --badsum=TYPE
[ATA only] Specifies the action smartctl should take if a check-
sum error is detected in the: (1) Device Identity Structure, (2)
SMART Self-Test Log Structure, (3) SMART Attribute Value Struc-
ture, (4) SMART Attribute Threshold Structure, or (5) ATA Error
The valid arguments to this option are:
warn - report the incorrect checksum but carry on in spite of
it. This is the default.
exit - exit smartctl.
ioctl - report all ioctl() transactions.
ataioctl - report only ioctl() transactions with ATA devices.
scsiioctl - report only ioctl() transactions with SCSI devices.
Invoking this once shows the SCSI commands in hex and the corre-
sponding status. Invoking it a second time adds a hex listing of
the first 64 bytes of data send to, or received from the device.
Any argument may include a positive integer to specify the level
of detail that should be reported. The argument should be fol-
lowed by a comma then the integer with no spaces. For example,
ataioctl,2 The default level is 1, so '-r ataioctl,1' and '-r
ataioctl' are equivalent.
For testing purposes, the output of '-r ataioctl,2' can later be
parsed by smartctl itself if '-' is used as device path argu-
ment. The ATA command input parameters, sector data and return
values are reconstructed from the debug report read from stdin.
Then smartctl internally simulates an ATA device with the same
behaviour. This is does not work for SCSI devices yet.
-n POWERMODE, --nocheck=POWERMODE
[ATA only] Specifies if smartctl should exit before performing
any checks when the device is in a low-power mode. It may be
used to prevent a disk from being spun-up by smartctl. The power
mode is ignored by default. A nonzero exit status is returned
if the device is in one of the specified low-power modes (see
RETURN VALUES below).
Note: If this option is used it may also be necessary to specify
the device type with the '-d' option. Otherwise the device may
spin up due to commands issued during device type autodetection.
The valid arguments to this option are:
never - check the device always, but print the power mode if
'-i' is specified.
sleep - check the device unless it is in SLEEP mode.
standby - check the device unless it is in SLEEP or STANDBY
mode. In these modes most disks are not spinning, so if you
want to prevent a disk from spinning up, this is probably what
idle - check the device unless it is in SLEEP, STANDBY or IDLE
mode. In the IDLE state, most disks are still spinning, so this
is probably not what you want.
SMART FEATURE ENABLE/DISABLE COMMANDS:
Note: if multiple options are used to both enable and disable a
-o VALUE, --offlineauto=VALUE
[ATA only] Enables or disables SMART automatic offline test,
which scans the drive every four hours for disk defects. This
command can be given during normal system operation. The valid
arguments to this option are on and off.
Note that the SMART automatic offline test command is listed as
"Obsolete" in every version of the ATA and ATA/ATAPI Specifica-
tions. It was originally part of the SFF-8035i Revision 2.0
specification, but was never part of any ATA specification.
However it is implemented and used by many vendors. [Good docu-
mentation can be found in IBM's Official Published Disk Specifi-
cations. For example the IBM Travelstar 40GNX Hard Disk Drive
Specifications (Revision 1.1, 22 April 2002, Publication # 1541,
Document S07N-7715-02) page 164. You can also read the SFF-8035i
Specification -- see REFERENCES below.] You can tell if auto-
matic offline testing is supported by seeing if this command
enables and disables it, as indicated by the 'Auto Offline Data
Collection' part of the SMART capabilities report (displayed
SMART provides three basic categories of testing. The first
category, called "online" testing, has no effect on the perfor-
mance of the device. It is turned on by the '-s on' option.
The second category of testing is called "offline" testing. This
type of test can, in principle, degrade the device performance.
The '-o on' option causes this offline testing to be carried
out, automatically, on a regular scheduled basis. Normally, the
disk will suspend offline testing while disk accesses are taking
place, and then automatically resume it when the disk would oth-
erwise be idle, so in practice it has little effect. Note that
a one-time offline test can also be carried out immediately upon
receipt of a user command. See the '-t offline' option below,
which causes a one-time offline test to be carried out immedi-
The choice (made by the SFF-8035i and ATA specification authors)
of the word testing for these first two categories is unfortu-
nate, and often leads to confusion. In fact these first two
categories of online and offline testing could have been more
accurately described as online and offline data collection.
The results of this automatic or immediate offline testing (data
collection) are reflected in the values of the SMART Attributes.
Thus, if problems or errors are detected, the values of these
Attributes will go below their failure thresholds; some types of
errors may also appear in the SMART error log. These are visible
with the '-A' and '-l error' options respectively.
Some SMART attribute values are updated only during off-line
data collection activities; the rest are updated during normal
Any errors detected in the self testing will be shown in the
SMART self-test log, which can be examined using the '-l self-
Note: in this manual page, the word "Test" is used in connection
with the second category just described, e.g. for the "offline"
testing. The words "Self-test" are used in connection with the
-S VALUE, --saveauto=VALUE
[ATA] Enables or disables SMART autosave of device vendor-spe-
cific Attributes. The valid arguments to this option are on and
off. Note that this feature is preserved across disk power
cycles, so you should only need to issue it once.
The ATA standard does not specify a method to check whether
SMART autosave is enabled. Unlike SCSI (below), smartctl is
unable to print a warning if autosave is disabled.
[SCSI] For SCSI devices this toggles the value of the Global
Logging Target Save Disabled (GLTSD) bit in the Control Mode
Page. Some disk manufacturers set this bit by default. This pre-
vents error counters, power-up hours and other useful data from
being placed in non-volatile storage, so these values may be
reset to zero the next time the device is power-cycled. If the
GLTSD bit is set then 'smartctl -a' will issue a warning. Use on
to clear the GLTSD bit and thus enable saving counters to
non-volatile storage. For extreme streaming-video type applica-
tions you might consider using off to set the GLTSD bit.
SMART READ AND DISPLAY DATA OPTIONS:
Check: Ask the device to report its SMART health status or pend-
ing TapeAlert messages. SMART status is based on information
that it has gathered from online and offline tests, which were
used to determine/update its SMART vendor-specific Attribute
values. TapeAlert status is obtained by reading the TapeAlert
If the device reports failing health status, this means either
that the device has already failed, or that it is predicting its
own failure within the next 24 hours. If this happens, use the
'-a' option to get more information, and get your data off the
disk and to someplace safe as soon as you can.
[ATA only] Prints only the generic SMART capabilities. These
show what SMART features are implemented and how the device will
respond to some of the different SMART commands. For example it
shows if the device logs errors, if it supports offline surface
scanning, and so on. If the device can carry out self-tests,
[ATA] Prints only the vendor specific SMART Attributes. The
Attributes are numbered from 1 to 253 and have specific names
and ID numbers. For example Attribute 12 is "power cycle count":
how many times has the disk been powered up.
Each Attribute has a "Raw" value, printed under the heading
"RAW_VALUE", and a "Normalized" value printed under the heading
"VALUE". [Note: smartctl prints these values in base-10.] In
the example just given, the "Raw Value" for Attribute 12 would
be the actual number of times that the disk has been
power-cycled, for example 365 if the disk has been turned on
once per day for exactly one year. Each vendor uses their own
algorithm to convert this "Raw" value to a "Normalized" value in
the range from 1 to 254. Please keep in mind that smartctl only
reports the different Attribute types, values, and thresholds as
read from the device. It does not carry out the conversion
between "Raw" and "Normalized" values: this is done by the
The conversion from Raw value to a quantity with physical units
is not specified by the SMART standard. In most cases, the val-
ues printed by smartctl are sensible. For example the tempera-
ture Attribute generally has its raw value equal to the tempera-
ture in Celsius. However in some cases vendors use unusual con-
ventions. For example the Hitachi disk on my laptop reports its
power-on hours in minutes, not hours. Some IBM disks track three
temperatures rather than one, in their raw values. And so on.
Each Attribute also has a Threshold value (whose range is 0 to
255) which is printed under the heading "THRESH". If the Nor-
malized value is less than or equal to the Threshold value, then
the Attribute is said to have failed. If the Attribute is a
pre-failure Attribute, then disk failure is imminent.
Each Attribute also has a "Worst" value shown under the heading
"WORST". This is the smallest (closest to failure) value that
the disk has recorded at any time during its lifetime when SMART
was enabled. [Note however that some vendors firmware may actu-
ally increase the "Worst" value for some "rate-type"
The Attribute table printed out by smartctl also shows the
"TYPE" of the Attribute. Attributes are one of two possible
types: Pre-failure or Old age. Pre-failure Attributes are ones
which, if less than or equal to their threshold values, indicate
pending disk failure. Old age, or usage Attributes, are ones
which indicate end-of-product life from old-age or normal aging
and wearout, if the Attribute value is less than or equal to the
threshold. Please note: the fact that an Attribute is of type
'Pre-fail' does not mean that your disk is about to fail! It
only has this meaning if the Attribute's current Normalized
value is less than or equal to the threshold value.
So to summarize: the Raw Attribute values are the ones that
might have a real physical interpretation, such as "Temperature
Celsius", "Hours", or "Start-Stop Cycles". Each manufacturer
converts these, using their detailed knowledge of the disk's
operations and failure modes, to Normalized Attribute values in
the range 1-254. The current and worst (lowest measured) of
these Normalized Attribute values are stored on the disk, along
with a Threshold value that the manufacturer has determined will
indicate that the disk is going to fail, or that it has exceeded
its design age or aging limit. smartctl does not calculate any
of the Attribute values, thresholds, or types, it merely reports
them from the SMART data on the device.
Note that starting with ATA/ATAPI-4, revision 4, the meaning of
these Attribute fields has been made entirely vendor-specific.
However most ATA/ATAPI-5 disks seem to respect their meaning, so
we have retained the option of printing the Attribute values.
[SCSI] For SCSI devices the "attributes" are obtained from the
temperature and start-stop cycle counter log pages. Certain ven-
dor specific attributes are listed if recognised. The attributes
are output in a relatively free format (compared with ATA disk
-f FORMAT, --format=FORMAT
[ATA only] Selects the output format of the attributes to one
old - Old smartctl format. This is the default unless the '-x'
option is specified.
brief - New format which fits into 80 colums (except in some
rare cases). This format also decodes four additional attribute
flags. This is the default if the '-x' option is specified.
-l TYPE, --log=TYPE
Prints either the SMART Error Log, the SMART Self-Test Log, the
SMART Selective Self-Test Log [ATA only], the Log Directory [ATA
only], or the Background Scan Results Log [SCSI only]. The
valid arguments to this option are:
error - [ATA] prints the Summary SMART error log. SMART disks
maintain a log of the most recent five non-trivial errors. For
each of these errors, the disk power-on lifetime at which the
error occurred is recorded, as is the device status (idle,
standby, etc) at the time of the error. For some common types
of errors, the Error Register (ER) and Status Register (SR) val-
ues are decoded and printed as text. The meanings of these are:
ABRT: Command ABoRTed
AMNF: Address Mark Not Found
CCTO: Command Completion Timed Out
EOM: End Of Media
ICRC: Interface Cyclic Redundancy Code (CRC) error
Dd+HH:MM:SS.msec where D is the number of days, HH is hours, MM
is minutes, SS is seconds and msec is milliseconds. [Note: this
time stamp wraps after 2^32 milliseconds, or 49 days 17 hours 2
minutes and 47.296 seconds.] The key ATA disk registers are
also recorded in the log. The final column of the error log is
a text-string description of the ATA command defined by the Com-
mand Register (CR) and Feature Register (FR) values. Commands
that are obsolete in the most current (ATA-7) spec are listed
like this: READ LONG (w/ retry) [OBS-4], indicating that the
command became obsolete with or in the ATA-4 specification.
Similarly, the notation [RET-N] is used to indicate that a com-
mand was retired in the ATA-N specification. Some commands are
not defined in any version of the ATA specification but are in
common use nonetheless; these are marked [NS], meaning non-stan-
The ATA Specification (ATA-5 Revision 1c, Section 220.127.116.11.2)
says: "Error log structures shall include UNC errors, IDNF
errors for which the address requested was valid, servo errors,
write fault errors, etc. Error log data structures shall not
include errors attributed to the receipt of faulty commands such
as command codes not implemented by the device or requests with
invalid parameters or invalid addresses." The definitions of
these terms are:
UNC (UNCorrectable): data is uncorrectable. This refers to data
which has been read from the disk, but for which the Error
Checking and Correction (ECC) codes are inconsistent. In
effect, this means that the data can not be read.
IDNF (ID Not Found): user-accessible address could not be found.
For READ LOG type commands, IDNF can also indicate that a device
data log structure checksum was incorrect.
If the command that caused the error was a READ or WRITE com-
mand, then the Logical Block Address (LBA) at which the error
occurred will be printed in base 10 and base 16. The LBA is a
linear address, which counts 512-byte sectors on the disk,
starting from zero. (Because of the limitations of the SMART
error log, if the LBA is greater than 0xfffffff, then either no
error log entry will be made, or the error log entry will have
an incorrect LBA. This may happen for drives with a capacity
greater than 128 GiB or 137 GB.) On Linux systems the smartmon-
tools web page has instructions about how to convert the LBA
address to the name of the disk file containing the erroneous
Please note that some manufacturers ignore the ATA specifica-
tions, and make entries in the error log if the device receives
a command which is not implemented or is not valid.
error - [SCSI] prints the error counter log pages for reads,
write and verifies. The verify row is only output if it has an
element other than zero.
xerror[,NUM][,error] - [ATA only] prints the Extended Comprehen-
If ',error' is appended and the Extended Comprehensive SMART
error log is not supported, the Summary SMART self-test log is
Please note that some recent (e.g. Samsung) drives report errors
only in the Extended Comprehensive SMART error log. The Summary
SMART error log can be read but is always empty.
selftest - [ATA] prints the SMART self-test log. The disk main-
tains a self-test log showing the results of the self tests,
which can be run using the '-t' option described below. For
each of the most recent twenty-one self-tests, the log shows the
type of test (short or extended, off-line or captive) and the
final status of the test. If the test did not complete success-
fully, then the percentage of the test remaining is shown. The
time at which the test took place, measured in hours of disk
lifetime, is also printed. [Note: this time stamp wraps after
2^16 hours, or 2730 days and 16 hours, or about 7.5 years.] If
any errors were detected, the Logical Block Address (LBA) of the
first error is printed in decimal notation. On Linux systems
the smartmontools web page has instructions about how to convert
this LBA address to the name of the disk file containing the
selftest - [SCSI] the self-test log for a SCSI device has a
slightly different format than for an ATA device. For each of
the most recent twenty self-tests, it shows the type of test and
the status (final or in progress) of the test. SCSI standards
use the terms "foreground" and "background" (rather than ATA's
corresponding "captive" and "off-line") and "short" and "long"
(rather than ATA's corresponding "short" and "extended") to
describe the type of the test. The printed segment number is
only relevant when a test fails in the third or later test seg-
ment. It identifies the test that failed and consists of either
the number of the segment that failed during the test, or the
number of the test that failed and the number of the segment in
which the test was run, using a vendor-specific method of
putting both numbers into a single byte. The Logical Block
Address (LBA) of the first error is printed in hexadecimal nota-
tion. On Linux systems the smartmontools web page has instruc-
tions about how to convert this LBA address to the name of the
disk file containing the erroneous block. If provided, the SCSI
Sense Key (SK), Additional Sense Code (ASC) and Additional Sense
Code Qualifier (ASQ) are also printed. The self tests can be run
using the '-t' option described below (using the ATA test termi-
xselftest[,NUM][,selftest] - [ATA only] prints the Extended
SMART self-test log (General Purpose Log address 0x07). Unlike
the SMART self-test log (see '-l selftest' above), it supports
48-bit LBA and logs with more than one sector. Each sector
holds up to 19 log entries. The actual number of log sectors is
vendor specific, typical values are 1 (Seagate) or 2 (Samsung).
tested is also displayed. The selective self-test log also
shows if a read-scan of the remainder of the disk will be car-
ried out after the selective self-test has completed (see '-t
afterselect' option) and the time delay before restarting this
read-scan if it is interrupted (see '-t pending' option). This
is a new smartmontools feature; please report unusual or incor-
rect behavior to the smartmontools-support mailing list.
directory[,gs] - [ATA only] if the device supports the General
Purpose Logging feature set (ATA-6 and above) then this prints
the Log Directory (the log at address 0). The Log Directory
shows what logs are available and their length in sectors (512
bytes). The contents of the logs at address 1 [Summary SMART
error log] and at address 6 [SMART self-test log] may be printed
using the previously-described error and selftest arguments to
this option. If your version of smartctl supports 48-bit ATA
commands, both the General Purpose Log (GPL) and SMART Log (SL)
directories are printed in one combined table. The output can be
restricted to the GPL directory or SL directory by '-l direc-
tory,q' or '-l directory,s' respectively.
background - [SCSI only] the background scan results log outputs
information derived from Background Media Scans (BMS) done after
power up and/or periodocally (e.g. every 24 hours) on recent
SCSI disks. If supported, the BMS status is output first, indi-
cating whether a background scan is currently underway (and if
so a progress percentage), the amount of time the disk has been
powered up and the number of scans already completed. Then there
is a header and a line for each background scan "event". These
will typically be either recovered or unrecoverable errors. That
latter group may need some attention. There is a description of
the background scan mechansim in section 4.18 of SBC-3 revision
6 (see www.t10.org ).
scttemp, scttempsts, scttemphist - [ATA only] prints the disk
temperature information provided by the SMART Command Transport
(SCT) commands. The option 'scttempsts' prints current tempera-
ture and temperature ranges returned by the SCT Status command,
'scttemphist' prints temperature limits and the temperature his-
tory table returned by the SCT Data Table command, and 'scttemp'
prints both. The temperature values are preserved across power
cycles. The default temperature logging interval is 1 minute
and can be configured with the '-t scttempint,N[,p]' option, see
below. The SCT commands are specified in the proposed ATA-8
Command Set (ACS), and are already implemented in some recent
scterc[,READTIME,WRITETIME] - [ATA only] [NEW EXPERIMENTAL
SMARTCTL FEATURE] prints values and descriptions of the SCT
Error Recovery Control settings. These are equivalent to TLER
(as used by Western Digital), CCTL (as used by Samsung and
Hitachi) and ERC (as used by Seagate). READTIME and WRITETIME
arguments (deciseconds) set the specified values. Values of 0
disable the feature, other values less than 65 are probably not
gplog,ADDR[,FIRST[-LAST|+SIZE]] - [ATA only] prints a hex dump
of any log accessible via General Purpose Logging (GPL) feature.
The log address ADDR is the hex address listed in the log direc-
tory (see '-l directory' above). The range of log sectors
(pages) can be specified by decimal values FIRST-LAST or
FIRST+SIZE. FIRST defaults to 0, SIZE defaults to 1. LAST can
be set to 'max' to specify the last page of the log.
smartlog,ADDR[,FIRST[-LAST|+SIZE]] - [ATA only] prints a hex
dump of any log accessible via SMART Read Log command. See '-l
gplog,...' above for parameter syntax.
For example, all these commands:
smartctl -l gplog,0x80,10-15 /dev/sda
smartctl -l gplog,0x80,10+6 /dev/sda
smartctl -l smartlog,0x80,10-15 /dev/sda
print pages 10-15 of log 0x80 (first host vendor specific log).
The hex dump format is compatible with the 'xxd -r' command.
smartctl -l gplog,0x11 /dev/sda | grep ^0 | xxd -r >log.bin
writes a binary representation of the one sector log 0x11 (SATA
Phy Event Counters) to file log.bin.
-v ID,FORMAT[:BYTEORDER][,NAME], --vendorattribute=ID,FORMAT[:BYTE-
[ATA only] Sets a vendor-specific raw value print FORMAT, an
optional BYTEORDER and an optional NAME for Attribute ID. This
option may be used multiple times.
The Attribute ID can be in the range 1 to 255. If 'N' is speci-
fied as ID, the settings for all Attributes are changed.
The optional BYTEORDER consists of 1 to 8 characters from the
set '012345rvwz'. The characters '0' to '5' select the byte 0 to
5 from the 48-bit raw value, 'r' selects the reserved byte of
the attribute data block, 'v' selects the normalized value, 'w'
selects the worst value and 'z' inserts a zero byte. The
default BYTEORDER is '543210' for all 48-bit formats, 'r543210'
for the 54-bit formats, and '543210wv' for the 64-bit formats.
For example, '-v 5,raw48:012345' prints the raw value of
attribute 5 with big endian instead of little endian byte order-
The NAME is a string of letters, digits and underscore.
-v help - Prints (to STDOUT) a list of all valid arguments to
this option, then exits.
Valid arguments for FORMAT are:
raw8 - Print the Raw value as six 8-bit unsigned base-10 inte-
gers. This may be useful for decoding the meaning of the Raw
raw64 - Print the Raw value as a 64-bit unsigned base-10 inte-
ger. This includes two bytes from the normalized and worst
attribute value. This new raw format is used by some recent SSD
hex64 - Print the Raw value as a 16 digit hexadecimal number.
This includes two bytes from the normalized and worst attribute
value. This new raw format is used by some recent SSD devices.
min2hour - Raw Attribute is power-on time in minutes. Its raw
value will be displayed in the form "Xh+Ym". Here X is hours,
and Y is minutes in the range 0-59 inclusive. Y is always
printed with two digits, for example "06" or "31" or "00".
sec2hour - Raw Attribute is power-on time in seconds. Its raw
value will be displayed in the form "Xh+Ym+Zs". Here X is
hours, Y is minutes in the range 0-59 inclusive, and Z is sec-
onds in the range 0-59 inclusive. Y and Z are always printed
with two digits, for example "06" or "31" or "00".
halfmin2hour - Raw Attribute is power-on time, measured in units
of 30 seconds. This format is used by some Samsung disks. Its
raw value will be displayed in the form "Xh+Ym". Here X is
hours, and Y is minutes in the range 0-59 inclusive. Y is
always printed with two digits, for example "06" or "31" or
msec24hour32 - Raw Attribute is power-on time measured in 32-bit
hours and 24-bit milliseconds since last hour update. It will
be displayed in the form "Xh+Ym+Z.Ms". Here X is hours, Y is
minutes, Z is seconds and M is milliseconds.
tempminmax - Raw Attribute is the disk temperature in Celsius.
Info about Min/Max temperature is printed if available. This is
the default for Attributes 190 and 194. The recording interval
(lifetime, last power cycle, last soft reset) of the min/max
values is device specific.
temp10x - Raw Attribute is ten times the disk temperature in
raw16(raw16) - Print the raw attribute as a 16-bit value and two
optional 16-bit values if these words are nonzero. This is the
default for Attributes 5 and 196.
raw16(avg16) - Raw attribute is spin-up time. It is printed as
a 16-bit value and an optional "Average" 16-bit value if the
word is nonzero. This is the default for Attribute 3.
raw24/raw24 - Raw Attribute contains two 24-bit values. The
first is the number of load cycles. The second is the number of
unload cycles. The difference between these two values is the
number of times that the drive was unexpectedly powered off
(also called an emergency unload). As a rule of thumb, the
9,halfminutes - same as: 9,halfmin2hour,Power_On_Half_Minutes.
9,temp - same as: 9,tempminmax,Temperature_Celsius.
192,emergencyretractcyclect - same as:
193,loadunload - same as: 193,raw24/raw24.
194,10xCelsius - same as: 194,temp10x,Temperature_Celsius_x10.
194,unknown - same as: 194,raw48,Unknown_Attribute.
197,increasing - same as: 197,raw48,Total_Pending_Sectors. Also
means that Attribute number 197 (Current Pending Sector Count)
is not reset if uncorrectable sectors are reallocated (see
smartd.conf(5) man page).
198,increasing - same as: 198,raw48,Total_Offl_Uncorrectabl.
Also means that Attribute number 198 (Offline Uncorrectable Sec-
tor Count) is not reset if uncorrectable sectors are reallocated
(see smartd.conf(5) man page).
198,offlinescanuncsectorct - same as: 198,raw48,Off-
200,writeerrorcount - same as: 200,raw48,Write_Error_Count.
201,detectedtacount - same as: 201,raw48,Detected_TA_Count.
220,temp - same as: 220,raw48,Temperature_Celsius.
Note: a table of hard drive models, listing which Attribute cor-
responds to temperature, can be found at:
-F TYPE, --firmwarebug=TYPE
[ATA only] Modifies the behavior of smartctl to compensate for
some known and understood device firmware or driver bug. Except
'swapid', the arguments to this option are exclusive, so that
only the final option given is used. The valid values are:
none - Assume that the device firmware obeys the ATA specifica-
tions. This is the default, unless the device has presets for
'-F' in the device database (see note below).
samsung - In some Samsung disks (example: model SV4012H Firmware
Version: RM100-08) some of the two- and four-byte quantities in
the SMART data structures are byte-swapped (relative to the ATA
specification). Enabling this option tells smartctl to evaluate
these quantities in byte-reversed order. Some signs that your
disk needs this option are (1) no self-test log printed, even
though you have run self-tests; (2) very large numbers of ATA
errors reported in the ATA error log; (3) strange and impossible
VF100-37) report a self-test still in progress with 0% remaining
when the test was already completed. Enabling this option modi-
fies the output of the self-test execution status (see options
'-c' or '-a' above) accordingly.
Note that an explicit '-F' option on the command line will
over-ride any preset values for '-F' (see the '-P' option
swapid - Fixes byte swapped ATA identify strings (device name,
serial number, firmware version) returned by some buggy device
-P TYPE, --presets=TYPE
[ATA only] Specifies whether smartctl should use any preset
options that are available for this drive. By default, if the
drive is recognized in the smartmontools database, then the pre-
sets are used.
smartctl can automatically set appropriate options for known
drives. For example, the Maxtor 4D080H4 uses Attribute 9 to
stores power-on time in minutes whereas most drives use that
Attribute to store the power-on time in hours. The command-line
option '-v 9,minutes' ensures that smartctl correctly interprets
Attribute 9 in this case, but that option is preset for the Max-
tor 4D080H4 and so need not be specified by the user on the
smartctl command line.
The argument show will show any preset options for your drive
and the argument showall will show all known drives in the
smartmontools database, along with their preset options. If
there are no presets for your drive and you think there should
be (for example, a -v or -F option is needed to get smartctl to
display correct values) then please contact the smartmontools
developers so that this information can be added to the smart-
montools database. Contact information is at the end of this
The valid arguments to this option are:
use - if a drive is recognized, then use the stored presets for
it. This is the default. Note that presets will NOT over-ride
additional Attribute interpretation ('-v N,something') com-
mand-line options or explicit '-F' command-line options..
ignore - do not use presets.
show - show if the drive is recognized in the database, and if
so, its presets, then exit.
showall - list all recognized drives, and the presets that are
set for them, then exit.
The '-P showall' option takes up to two optional arguments to
then the new entries prepend the built in entries.
If this option is not specified, optional entries are read from
the file /etc/smart_drivedb.h (Windows: EXEDIR/drivedb-add.h).
If /usr/share/smartmontools/drivedb.h (Windows:
EXEDIR/drivedb.h) is present, the contents of this file is used
instead of the built in table.
Run the script /usr/sbin/update-smart-drivedb to update this
file from the smartmontools SVN repository.
The database files use the same C/C++ syntax that is used to
initialize the built in database array. C/C++ style comments are
/* Full entry: */
"Model family", // Info about model family/series.
"MODEL1.*REGEX", // Regular expression to match model of device.
"VERSION.*REGEX", // Regular expression to match firmware version(s).
"Some warning", // Warning message.
"-v 9,minutes" // String of preset -v and -F options.
/* Minimal entry: */
"", // No model family/series info.
"MODEL2.*REGEX", // Regular expression to match model of device.
"", // All firmware versions.
"", // No warning.
"" // No options preset.
/* USB ID entry: */
"USB: Device; Bridge", // Info about USB device and bridge name.
"0x1234:0xabcd", // Regular expression to match vendor:product ID.
"0x0101", // Regular expression to match bcdDevice.
"", // Not used.
"-d sat" // String with device type option.
/* ... */
SMART RUN/ABORT OFFLINE TEST AND SELF-TEST OPTIONS:
-t TEST, --test=TEST
Executes TEST immediately. The '-C' option can be used in con-
junction with this option to run the short or long (and also for
ATA devices, selective or conveyance) self-tests in captive mode
(known as "foreground mode" for SCSI devices). Note that only
one test type can be run at a time, so only one test type should
be specified per command line. Note also that if a computer is
shutdown or power cycled during a self-test, no harm should
result. The self-test will either be aborted or will resume
you can track the progress of the Immediate Offline test using
the '-c' option to smartctl. If the '-c' option show that the
device has the "Abort Offline collection upon new command" capa-
bility then most commands will abort the Immediate Offline Test,
so you should not try to track the progress of the test with
'-c', as it will abort the test.
offline - [SCSI] runs the default self test in foreground. No
entry is placed in the self test log.
short - [ATA] runs SMART Short Self Test (usually under ten min-
utes). This command can be given during normal system operation
(unless run in captive mode - see the '-C' option below). This
is a test in a different category than the immediate or auto-
matic offline tests. The "Self" tests check the electrical and
mechanical performance as well as the read performance of the
disk. Their results are reported in the Self Test Error Log,
readable with the '-l selftest' option. Note that on some disks
the progress of the self-test can be monitored by watching this
log during the self-test; with other disks use the '-c' option
to monitor progress.
short - [SCSI] runs the "Background short" self-test.
long - [ATA] runs SMART Extended Self Test (tens of minutes).
This is a longer and more thorough version of the Short Self
Test described above. Note that this command can be given dur-
ing normal system operation (unless run in captive mode - see
the '-C' option below).
long - [SCSI] runs the "Background long" self-test.
conveyance - [ATA only] runs a SMART Conveyance Self Test (min-
utes). This self-test routine is intended to identify damage
incurred during transporting of the device. This self-test rou-
tine should take on the order of minutes to complete. Note that
this command can be given during normal system operation (unless
run in captive mode - see the '-C' option below).
select,N-M, select,N+SIZE - [ATA only] runs a SMART Selective
Self Test, to test a range of disk Logical Block Addresses
(LBAs), rather than the entire disk. Each range of LBAs that is
checked is called a "span" and is specified by a starting LBA
(N) and an ending LBA (M) with N less than or equal to M. The
range can also be specified as N+SIZE. A span at the end of a
disk can be specified by N-max.
For example the commands:
smartctl -t select,10-20 /dev/hda
smartctl -t select,10+11 /dev/hda
both runs a self test on one span consisting of LBAs ten to
twenty (inclusive). The command:
smartctl -t select,100000000-max /dev/hda
run a self test from LBA 100000000 up to the end of the disk.
increase: an extended self test (smartctl -t long) can take sev-
eral hours. Selective self-tests are helpful if (based on SYS-
LOG error messages, previous failed self-tests, or SMART error
log entries) you suspect that a disk is having problems at a
particular range of Logical Block Addresses (LBAs).
Selective self-tests can be run during normal system operation
(unless done in captive mode - see the '-C' option below).
The following variants of the selective self-test command use
spans based on the ranges from past tests already stored on the
select,redo[+SIZE] - [ATA only] redo the last SMART Selective
Self Test using the same LBA range. The starting LBA is identi-
cal to the LBA used by last test, same for ending LBA unless a
new span size is specified by optional +SIZE argument.
For example the commands:
smartctl -t select,10-20 /dev/hda
smartctl -t select,redo /dev/hda
smartctl -t select,redo+20 /dev/hda
have the same effect as:
smartctl -t select,10-20 /dev/hda
smartctl -t select,10-20 /dev/hda
smartctl -t select,10-29 /dev/hda
select,next[+SIZE] - [ATA only] runs a SMART Selective Self Test
on the LBA range which follows the range of the last test. The
starting LBA is set to (ending LBA +1) of the last test. A new
span size may be specified by the optional +SIZE argument.
For example the commands:
smartctl -t select,0-999 /dev/hda
smartctl -t select,next /dev/hda
smartctl -t select,next+2000 /dev/hda
have the same effect as:
smartctl -t select,0-999 /dev/hda
smartctl -t select,1000-1999 /dev/hda
smartctl -t select,2000-3999 /dev/hda
If the last test ended at the last LBA of the disk, the new
range starts at LBA 0. The span size of the last span of a disk
is adjusted such that the total number of spans to check the
full disk will not be changed by future uses of '-t
select,cont[+SIZE] - [ATA only] performs a 'redo' (above) if the
self test status reports that the last test was aborted by the
host. Otherwise it run the 'next' (above) test.
afterselect,on - [ATA only] perform an offline read scan after a
Selective Self-test has completed. This option must be used
together with one or more of the select,N-M options above. If
pending,N - [ATA only] set the pending offline read scan timer
to N minutes. Here N is an integer in the range from 0 to 65535
inclusive. If the device is powered off during a read scan
after a Selective self-test, then resume the test automatically
N minutes after power-up. This option must be use together with
one or more of the select,N-M options above. The value of this
option is preserved between selective self-tests.
scttempint,N[,p] - [ATA only] set the time interval for SCT tem-
perature logging to N minutes. If ',p' is specified, the setting
is preserved across power cycles. Otherwise, the setting is
volatile and will be reverted to default (1 minute), or last
non-volatile setting by the next hard reset. This command also
clears the temperature history table. See '-l scttemp' above for
more information about SCT temperature logging.
vendor,N - [ATA only] issues the ATA command SMART EXECUTE OFF-
LINE IMMEDIATE with subcommand N in LBA LOW register. The sub-
command is specified as a hex value in the range 0x00 to 0xff.
Subcommands 0x40-0x7e and 0x90-0xff are reserved for vendor spe-
cific use, see table 61 of T13/1699-D Revision 6a (ATA8-ACS).
Note that the subcommands 0x00-0x04,0x7f,0x81-0x84 are supported
by other smartctl options (e.g. 0x01: '-t short', 0x7f: '-X',
0x82: '-C -t long').
WARNING: Only run subcommands documented by the vendor of the
Example for Intel (X18-M/X25-M G2 and 320 Series) SSDs only: The
subcommand 0x40 ('-t vendor,0x40') clears the timed workload
related SMART attributes (226, 227, 228). Note that the raw
values of these attributes are held at 65535 (0xffff) until the
workload timer reaches 60 minutes.
[ATA] Runs self-tests in captive mode. This has no effect with
'-t offline' or if the '-t' option is not used.
WARNING: Tests run in captive mode may busy out the drive for
the length of the test. Only run captive tests on drives with-
out any mounted partitions!
[SCSI] Runs the self-test in "Foreground" mode.
Aborts non-captive SMART Self Tests. Note that this command
will abort the Offline Immediate Test routine only if your disk
has the "Abort Offline collection upon new command" capability.
ATA, SCSI command sets and SAT
In the past there has been a clear distinction between storage devices
that used the ATA and SCSI command sets. This distinction was often
reflected in their device naming and hardware. Now various SCSI trans-
lents as the need arises. An important note here is that "lower level"
may be in external equipment and hence outside the control of an OS.
SCSI to ATA Translation (SAT) is a standard (ANSI INCITS 431-2007) that
specifies how this translation is done. For the other 1% of operations
that an OS performs on a disk, SAT provides two options. First is an
optional ATA PASS-THROUGH SCSI command (there are two variants). The
second is a translation from the closest SCSI command. Most current
interest is in the "pass-through" option.
The relevance to smartmontools (and hence smartctl) is that its inter-
actions with disks fall solidly into the "1%" category. So even if the
OS can happily treat (and name) a disk as "SCSI", smartmontools needs
to detect the native command set and act accordingly. As more storage
manufacturers (including external SATA drives) comply with SAT, smart-
montools is able to automatically distinguish the native command set of
the device. In some cases the '-d sat' option is needed on the command
There are also virtual disks which typically have no useful information
to convey to smartmontools, but could conceivably in the future. An
example of a virtual disk is the OS's view of a RAID 1 box. There are
most likely two SATA disks inside a RAID 1 box. Addressing those SATA
disks from a distant OS is a challenge for smartmontools. Another
approach is running a tool like smartmontools inside the RAID 1 box
(e.g. a Network Attached Storage (NAS) box) and fetching the logs via
smartctl -a /dev/hda
Print a large amount of SMART information for drive /dev/hda which is
typically an ATA (IDE) or SATA disk in Linux.
smartctl -a /dev/sdb
Print a large amount of SMART information for drive /dev/sdb . This may
be a SCSI disk or an ATA (SATA) disk.
smartctl -s off /dev/hdd
Disable SMART monitoring and data log collection on drive /dev/hdd .
smartctl --smart=on --offlineauto=on --saveauto=on /dev/hda
Enable SMART on drive /dev/hda, enable automatic offline testing every
four hours, and enable autosaving of SMART Attributes. This is a good
start-up line for your system's init files. You can issue this command
on a running system.
smartctl -t long /dev/hdc
Begin an extended self-test of drive /dev/hdc. You can issue this com-
mand on a running system. The results can be seen in the self-test log
visible with the '-l selftest' option after it has completed.
smartctl -s on -t offline /dev/hda
Enable SMART on the disk, and begin an immediate offline test of drive
/dev/hda. You can issue this command on a running system. The results
smartctl -q silent -a /dev/hda
Examine all SMART data for device /dev/hda, but produce no printed out-
put. You must use the exit status (the $? shell variable) to learn if
any Attributes are out of bound, if the SMART status is failing, if
there are errors recorded in the self-test log, or if there are errors
recorded in the disk error log.
smartctl -a -d 3ware,0 /dev/sda
Examine all SMART data for the first ATA disk connected to a 3ware RAID
smartctl -a -d 3ware,0 /dev/twe0
Examine all SMART data for the first ATA disk connected to a 3ware RAID
6000/7000/8000 controller card.
smartctl -a -d 3ware,0 /dev/twa0
Examine all SMART data for the first ATA disk connected to a 3ware RAID
9000 controller card.
smartctl -a -d 3ware,0 /dev/twl0
Examine all SMART data for the first SATA (not SAS) disk connected to a
3ware RAID 9750 controller card.
smartctl -t short -d 3ware,3 /dev/sdb
Start a short self-test on the fourth ATA disk connected to the 3ware
RAID controller card which is the second SCSI device /dev/sdb.
smartctl -t long -d areca,4 /dev/sg2
Start a long self-test on the fourth SATA disk connected to an Areca
RAID controller addressed by /dev/sg2.
smartctl -a -d hpt,1/3 /dev/sda (under Linux)
smartctl -a -d hpt,1/3 /dev/hptrr (under FreeBSD)
Examine all SMART data for the (S)ATA disk directly connected to the
third channel of the first HighPoint RocketRAID controller card.
smartctl -t short -d hpt,1/1/2 /dev/sda (under Linux)
smartctl -t short -d hpt,1/1/2 /dev/hptrr (under FreeBSD)
Start a short self-test on the (S)ATA disk connected to second pmport
on the first channel of the first HighPoint RocketRAID controller card.
smartctl -t select,10-100 -t select,30-300 -t afterselect,on -t pending,45 /dev/hda
Run a selective self-test on LBAs 10 to 100 and 30 to 300. After the
these LBAs have been tested, read-scan the remainder of the disk. If
the disk is power-cycled during the read-scan, resume the scan 45 min-
utes after power to the device is restored.
smartctl -a -d cciss,0 /dev/cciss/c0d0
Examine all SMART data for the first SCSI disk connected to a cciss
RAID controller card.
The return values of smartctl are defined by a bitmask. If all is well
with the disk, the return value (exit status) of smartctl is 0 (all
Bit 2: Some SMART command to the disk failed, or there was a checksum
error in a SMART data structure (see '-b' option above).
Bit 3: SMART status check returned "DISK FAILING".
Bit 4: We found prefail Attributes <= threshold.
Bit 5: SMART status check returned "DISK OK" but we found that some
(usage or prefail) Attributes have been <= threshold at some
time in the past.
Bit 6: The device error log contains records of errors.
Bit 7: The device self-test log contains records of errors. [ATA only]
Failed self-tests outdated by a newer successful extended
self-test are ignored.
To test within the shell for whether or not the different bits
are turned on or off, you can use the following type of con-
struction (this is bash syntax):
smartstat=$(($? & 8))
This looks at only at bit 3 of the exit status $? (since
8=2^3). The shell variable $smartstat will be nonzero if SMART
status check returned "disk failing" and zero otherwise.
The TapeAlert log page flags are cleared for the initiator when the
page is read. This means that each alert condition is reported only
once by smartctl for each initiator for each activation of the condi-
Bruce Allen firstname.lastname@example.org
University of Wisconsin - Milwaukee Physics Department
The following have made large contributions to smartmontools:
Casper Dik (Solaris SCSI interface)
Christian Franke (Windows interface, C++ redesign, USB support, ...)
Douglas Gilbert (SCSI subsystem)
Guido Guenther (Autoconf/Automake packaging)
Geoffrey Keating (Darwin ATA interface)
Eduard Martinescu (FreeBSD interface)
Frederic L. W. Meunier (Web site and Mailing list)
Gabriele Pohl (Web site and Wiki, conversion from CVS to SVN)
Keiji Sawada (Solaris ATA interface)
Manfred Schwarb (Drive database)
Sergey Svishchev (NetBSD interface)
David Snyder and Sergey Svishchev (OpenBSD interface)
Phil Williams (User interface and drive database)
Yuri Dario (OS/2, eComStation interface)
HOME PAGE FOR SMARTMONTOOLS:
Please see the following web site for updates, further documentation,
bug reports and patches: http://smartmontools.sourceforge.net/
smartd(8), badblocks(8), ide-smart(8).
REFERENCES FOR SMART
An introductory article about smartmontools is Monitoring Hard Disks
with SMART, by Bruce Allen, Linux Journal, January 2004, pages 74-77.
This is http://www.linuxjournal.com/article/6983 online.
If you would like to understand better how SMART works, and what it
does, a good place to start is with Sections 4.8 and 6.54 of the first
volume of the 'AT Attachment with Packet Interface-7' (ATA/ATAPI-7)
specification Revision 4b. This documents the SMART functionality
which the smartmontools utilities provide access to. This and other
versions of this Specification are available from the T13 web site
The functioning of SMART was originally defined by the SFF-8035i revi-
sion 2 and the SFF-8055i revision 1.4 specifications. These are publi-
cations of the Small Form Factors (SFF) Committee.
Links to these and other documents may be found on the Links page of
the smartmontools Wiki at http://sourceforge.net/apps/trac/smartmon-
SVN ID OF THIS PAGE:
$Id: smartctl.8.in 3320 2011-04-30 20:44:55Z chrfranke $
smartmontools-5.41 2011-06-09 SMARTCTL(8)
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