a program to manipulate ATA (IDE) devices
allows a user or system administrator
to issue commands to and otherwise control devices which reside on standard
IDE and ATA controllers. It is used by specifying a device to manipulate, a
command to perform, and any arguments the command may require.
supports the following commands:
acousticdisable, acousticset, apmdisable, apmset, checkpower, dump, identify
(the default), idle, poddisable, podenable, puisdisable, puisenable,
puisspinup, readaheaddisable, readaheadenable, readattr, secdisablepass,
secerase, secfreeze, secsetpass, secunlock, setidle, setstandby, sleep,
smartautosave, smartdisable, smartenable, smartoffline, smartread,
smartreadlog, smartstatus, standby, writecachedisable, and writecacheenable.
Support for Self-Monitoring, Analysis, and Reporting Technology (SMART)
functionality is indicated by the device with ‘SMART feature
set’ in the output of the
SMART commands and the
command are for
Support for Security Mode functionality is indicated by the device with
‘Security Mode feature set’ in the output of the
command. Be very
while playing with these commands: loss of the user and master
passwords for the device will result in an inaccessible device.
A full description of the commands follows:
- Disables support for automatic acoustic management on the specified
device. Note that devices supporting automatic acoustic management may
refuse to disable it, resulting in an ‘ATA device returned Aborted
- Enables and sets the automatic acoustic management level to the requested
level on the specified device (if supported). Device performance may
increase with increasing automatic acoustic management levels at the cost
of potentially generating more noise and requiring more power. Valid
values are 0 up to and including 126. Support for automatic acoustic
management is indicated by the device with ‘Automatic Acoustic
Management feature set’ in the output of the
- Disables support for advanced power management on the specified device.
Note that devices supporting advanced power management may refuse to
disable it, resulting in an ‘ATA device returned Aborted
- Enables and sets the advanced power management level to the requested
level on the specified device (if supported). Device performance may
increase with increasing power management levels at the cost of
potentially requiring more power. Values up to and including 126 allow the
device to go into standby mode and spin-down the disk. This
may cause disk time-outs and is therefore
not recommended. These values are more
suitable optimization for low power usage on infrequently used devices.
Values 127 up to and including 253 do not allow the device to go to
standby mode and are more suitable for optimization for performance.
Support for advanced power management is indicated by the device with
‘Advanced Power Management feature set’ in the output of the
- Will print out if the device is in Active, Idle, or Standby power
- Extracts the records about issued ATA commands from the log buffer. The
log buffer is cleared after extraction.
- Identify the specified device, displaying the device's vendor, product,
revision strings, supported capabilities and enabled capabilities. This
command is the default.
- Place the specified device into Idle mode. This mode may consume less
power than Active mode.
- Disallows the specified device to revert to power-on default (pod)
settings after a software reset. In other words this permits the settings
that have been modified since power-on to remain after a software reset.
- Allows the specified device to revert to power-on default (pod) settings
after a software reset.
- Disables power-up in standby (puis) on the specified device, causing the
device to spin up the disks after power-up. This should be the factory
default setting of the device and it is recommended to leave this setting
- Enables power-up in standby (puis) on the specified device, causing the
device to wait while spinning up the disks after power-up. This may cause
problems at boot if the device is too slow in spin-up. This option is
therefore not recommended unless the
implications are understood. Note that the power-up in standby mode stays
enabled over power-downs, hardware and software resets. Support for
power-up in standby is indicated by the device with ‘Power-up in
standby feature set’ in the output of the
- Explicitly spins up the device if power-up in standby (puis) mode is
- Disables read look-ahead on the specified device. This may decrease
performance. Note that the device may use ‘vendor specific’
behaviour in implementing this, so it is not
recommended to issue this command on a disk containing any currently
- Enables read look-ahead on the specified device. This may increase
performance. Support for and status of read look-ahead is indicated by the
device with ‘read look-ahead’ in the output of the
- Displays attribute thresholds and values for the specified device. Besides
attribute values, device vendors may provide additional information shown
in the last column, ``Raw''. Attributes names can be completely wrong
since they vary between vendors and even models, so don't rely on it.
SMART must be enabled while executing this command or the device will
return an error.
- Disables the lock mode for the specified device with user or master
password. This command won't change the master password. The master
password will be reactivated when a user password is set.
- Erases all user data and unlocks the specified device. Execution of this
command with the master password is the only way to unlock a device locked
at maximum security level with the
command if the user's password is lost or unknown. There are two erase
modes: normal and enhanced. Default erase mode is normal. In the normal
erase mode this command will write binary zeroes to all user data areas.
The enhanced erase mode is optional and may not be supported by the
device. When enhanced erase mode is specified, the device will write
predetermined data patterns to all user data areas. In enhanced erase
mode, all previously written user data will be overwritten, including
sectors that are no longer in use due to reallocation. This command will
disable the device lock mode, however, the master password will still be
stored internally within the device and may be reactivated later when a
new user password is set.
- Prevents changes to passwords until a following power cycle. The purpose
of this command is to prevent password setting attacks on the security
system. After command completion any other commands that update the device
lock mode will be aborted.
- Sets password and security level for the specified device. There are two
passwords, user and master, and two security levels, high and maximum. The
maximum password length is 32 symbols. The security system is enabled by
sending a user password to the device with this command. When the security
system is enabled, access to user data on the device is denied after a
power cycle until the user password is sent to the device with the
secunlock command. A master password may be set in
addition to the user password. The purpose of the master password is to
allow an administrator to establish a password that is kept secret from
the user, and which may be used to unlock the device if the user password
is lost. Setting the master password does not enable security system. Each
master password change decrements the master password revision code value
which is displayed in the
identify command output
if supported. After value 0x0001 is reached the next value will be 0xfffe.
The security level determines device behavior when the master password is
used to unlock the device. When the security level is set to high the
device requires the
secunlock command if the
master password is used to unlock. When the security level is set to
maximum the device requires a
secerase command if
the master password is used to unlock it. Execution of the
secerase command erases all user data on the
- Unlocks the specified device with user or master password. The device will
always unlock if a valid user password is received. If the security level
was set to high during the last
command, the device will unlock if the master password is received. If the
security level was set to maximum during the last
secsetpass command, the device won't unlock even
if the master password is received.
- Places the specified device into Idle mode, and sets the Idle timer to
idle-timer seconds. A value of 0 will
disable the Idle timer.
- Places the specified device into Standby mode, and sets the Standby timer
to standby-timer seconds. A value of 0
will disable the Standby timer.
- Place the specified device into Sleep mode. This mode will consume less
power than Standby mode, but requires a device reset to resume operation.
Typically the wd(4)
driver performs this reset automatically, but this should still be used
- Enables/disables attribute autosave feature on the specified device.
- Disables support for SMART on the specified device. Note that this means
that the device will no longer record any SMART information.
Note that SMART must be enabled while executing
the following commands or the device will return an error.
- Enables SMART (Self-Monitoring, Analysis, and Reporting Technology) on the
specified device (if supported). This causes the device to record
information for prediction of device degradation and/or faults.
- Causes the specified device to immediately initiate the optional set of
activities that collect SMART data in off-line mode and then save this
data to the device's non-volatile memory, or execute self-diagnostic test
routines in either captive or off-line mode. The
subcommand may be one of the following:
Note that executing self-test routines in captive mode causes the device to
be not accessible until the routine completes. This option is therefore
not recommended unless the implications are
- Abort off-line mode self-test routine.
- Start SMART off-line data collection immediately.
- Execute SMART extended self-test routine immediately in captive mode.
- Execute SMART extended self-test routine immediately in off-line mode.
- Execute SMART short self-test routine immediately in captive mode.
- Execute SMART short self-test routine immediately in off-line
- Reads various SMART information from the specified device and prints it to
- Reads specified log and prints it to
stdout. The log may be one of the
- The comprehensive error log.
- The error log directory.
- The self-test log.
- The summary error log.
- Reads the reliability status of the specified device. If the device
reports that one of its thresholds is exceeded (a strong indication of
imminent failure), the warning ‘SMART threshold exceeded!’
is printed to stderr and a status of 2 is returned.
- Place the specified device into Standby mode. This mode will consume less
power than Idle mode.
- Disable the write cache on the specified device (if supported). This may
decrease performance. Support for and status of write caching is indicated
by the device with ‘write cache’ in the output of the
- Enables the write cache on the specified device (if supported). This may
increase performance, however data still in the device's cache at
powerdown may be lost. The
performs a cache flush automatically before shutdown.
Display the vendor, product, revision strings, and capabilities (such as SMART
support) as reported by /dev/wd0
# atactl /dev/wd0c
Enable SMART support on /dev/wd0
detection of early warning signs of device failure:
# atactl /dev/wd0c
which queries /dev/wd0
each hour for early
warning signs of failure. If the device exceeds one of the SMART thresholds,
will output ‘SMART threshold
exceeded!’ to stderr and
will mail it.
0 * * * * /sbin/atactl /dev/wd0c
command first appeared in
. Support for acoustic management, advanced
power management, power-up in standby, read look-ahead, and SMART was added in
command was written by Ken
Hornstein. It was based heavily on the scsictl command written by Jason R.
Thorpe. Support for acoustic management, advanced power management, power-up
in standby, read look-ahead, and SMART was added by Wouter Slegers.
Not all devices are created equally. Some may not support the feature sets
and/or commands needed to perform the requested action, even when the
command indicates support for the requested
action. The device will typically respond with an ‘ATA device returned
Aborted Command’ if the requested action is not supported. Similarly a
device might not implement all commands in a feature set, so even though
disabling a feature works, enabling might not.
The output from the
command is rather ugly.
Disabling read look-ahead with
cause problems with mounted filesystems on that device.