| SMARTD(8) | SMART Monitoring Tools | SMARTD(8) |
smartd - SMART Disk Monitoring Daemon
smartd [options]
[This man page is generated for the Linux version of smartmontools. It does not contain info specific to other platforms.]
smartd is a daemon that monitors the Self-Monitoring, Analysis and Reporting Technology (SMART) system built into most ATA/SATA and SCSI/SAS hard drives and solid-state 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 smartd is compatible with ACS-3, ACS-2, ATA8-ACS, ATA/ATAPI-7 and earlier standards (see REFERENCES below).
smartd will attempt to enable SMART monitoring on ATA devices (equivalent to smartctl -s on) and polls these and SCSI devices every 30 minutes (configurable), logging SMART errors and changes of SMART Attributes via the SYSLOG interface. The default location for these SYSLOG notifications and warnings is system-dependent (typically /var/log/messages or /var/log/syslog). To change this default location, please see the '-l' command-line option described below.
In addition to logging to a file, smartd can also be configured to send email warnings if problems are detected. Depending upon the type of problem, you may want to run self-tests on the disk, back up the disk, replace the disk, or use a manufacturer's utility to force reallocation of bad or unreadable disk sectors. If disk problems are detected, please see the smartctl manual page and the smartmontools web page/FAQ for further guidance.
If you send a USR1 signal to smartd it will immediately check the status of the disks, and then return to polling the disks every 30 minutes. See the '-i' option below for additional details.
smartd can be configured at start-up using the
configuration file /etc/smartd.conf (Windows:
EXEDIR/smartd.conf). If the configuration file is subsequently
modified, smartd can be told to re-read the configuration file by
sending it a HUP signal, for example with the command:
killall -HUP smartd.
On startup, if smartd finds a syntax error in the configuration file, it will print an error message and then exit. However if smartd is already running, then is told with a HUP signal to re-read the configuration file, and then find a syntax error in this file, it will print an error message and then continue, ignoring the contents of the (faulty) configuration file, as if the HUP signal had never been received.
When smartd is running in debug mode, the INT signal (normally generated from a shell with CONTROL-C) is treated in the same way as a HUP signal: it makes smartd reload its configuration file. To exit smartd use CONTROL-\.
[Linux only] If smartd is started as a systemd(1) service and 'Type=Notify' is specified in the service file, the service manager is notified after successful startup. Other state changes are reported via systemd notify STATUS messages. Notification of successful reloads (after HUP signal) is not supported. To detect this process start-up type, smartd checks whether the environment variable 'NOTIFY_SOCKET' is set. Note that it is required to set the '-n' ('--nofork') option in the 'ExecStart=/usr/sbin/smartd' command line if 'Type=Notify' is used.
On startup, in the absence of the configuration file /etc/smartd.conf, the smartd daemon first scans for all devices that support SMART. The scanning is done as follows:
If directive '-d nvme' or no '-d' directive is specified, examine all entries "/dev/nvme[0-99]" for NVMe devices.
smartd then monitors for all possible SMART errors (corresponding to the '-a' Directive in the configuration file; see the smartd.conf(5) man page).
If this option is not specified, attribute information is
written to files '/var/lib/smartmontools/attrlog.MODEL-SERIAL.ata.csv'.
[NEW EXPERIMENTAL SMARTD FEATURE] If '-' is specified as the argument,
attribute log files are disabled.
MODEL and SERIAL are build from drive identify information, invalid characters are replaced by underline.
If the PREFIX has the form '/path/dir/' (e.g. '/var/lib/smartd/'), then files 'MODEL-SERIAL.ata.csv' are created in directory '/path/dir'. If the PREFIX has the form '/path/name' (e.g. '/var/lib/misc/attrlog-'), then files 'nameMODEL-SERIAL.ata.csv' are created in directory '/path/'. The path must be absolute, except if debug mode is enabled.
By using '-' for FILE, the configuration is read from standard
input. This is useful for commands like:
echo /dev/sdb -m user@home -M test | smartd -c - -q onecheck
to perform quick and simple checks without a configuration file.
[NEW EXPERIMENTAL SMARTD FEATURE] Mail notification is no longer suppressed if capabilities are dropped. It depends on the local MTA whether mail could be send from a root process with all capabilities dropped. It works with the postfix MTA.
If '--capabilities=mail' is specified, the following capabilities are added to the bounding set: CAP_SETGID, CAP_SETUID, CAP_CHOWN, CAP_FOWNER, CAP_DAC_OVERRIDE. This allows one to send mail with the exim MTA.
Note that the superuser can make smartd check the
status of the disks at any time by sending it the SIGUSR1 signal,
for example with the command:
kill -SIGUSR1 <pid>
where <pid> is the process id number of smartd. One
may also use:
killall -USR1 smartd
for the same purpose.
If you would like to have smartd messages logged somewhere other than the default location, include (for example) '-l local3' in its start up argument list. Tell the syslog daemon to log all messages from facility local3 to (for example) '/var/log/smartd.log'.
For more detailed information, please refer to the man pages for the local syslog daemon, typically syslogd(8), syslog-ng(8) or rsyslogd(8).
nodev - Exit if there are no devices to monitor, or if any errors are found at startup in the configuration file. This is the default.
errors - Exit if there are no devices to monitor, or if any errors are found in the configuration file /etc/smartd.conf at startup or whenever it is reloaded.
nodevstartup - Exit if there are no devices to monitor at startup. But continue to run if no devices are found whenever the configuration file is reloaded.
never - Only exit if a fatal error occurs (no remaining system memory, invalid command line arguments). In this mode, even if there are no devices to monitor, or if the configuration file /etc/smartd.conf has errors, smartd will continue to run, waiting to load a configuration file listing valid devices.
nodev0 - [NEW EXPERIMENTAL SMARTD FEATURE] Same as 'nodev', except that the exit status is 0 if there are no devices to monitor.
nodev0startup - [NEW EXPERIMENTAL SMARTD FEATURE] Same as 'nodevstartup', except that the exit status is 0 if there are no devices to monitor.
errors,nodev0 - [NEW EXPERIMENTAL SMARTD FEATURE] Same as 'errors', except that the exit status is 0 if there are no devices to monitor.
onecheck - Start smartd in debug mode, then register devices, then check device's SMART status once, and then exit with zero exit status if all of these steps worked correctly.
This last option is intended for 'distribution-writers' who want to create automated scripts to determine whether or not to automatically start up smartd after installing smartmontools. After starting smartd with this command-line option, the distribution's install scripts should wait a reasonable length of time (say ten seconds). If smartd has not exited with zero status by that time, the script should send smartd a SIGTERM or SIGKILL and assume that smartd will not operate correctly on the host. Conversely, if smartd exits with zero status, then it is safe to run smartd in normal daemon mode. If smartd is unable to monitor any devices or encounters other problems then it will return with non-zero exit status.
showtests - Start smartd in debug mode, then register devices, then write a list of future scheduled self tests to stdout, and then exit with zero exit status if all of these steps worked correctly. Device's SMART status is not checked.
This option is intended to test whether the '-s REGEX' directives in smartd.conf will have the desired effect. The output lists the next test schedules, limited to 5 tests per type and device. This is followed by a summary of all tests of each device within the next 90 days.
ioctl - report all ioctl() transactions.
ataioctl - report only ioctl() transactions with ATA devices.
scsiioctl - report only ioctl() transactions with SCSI devices.
nvmeioctl - report only ioctl() transactions with NVMe devices.
Any argument may include a positive integer to specify the level of detail that should be reported. The argument should be followed 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.
If this option is not specified, state information is
maintained in files
'/var/lib/smartmontools/smartd.MODEL-SERIAL.ata.state' for ATA devices
and '/var/lib/smartmontools/smartd.VENDOR-MODEL-SERIAL.scsi.state' for
SCSI devices.
[NEW EXPERIMENTAL SMARTD FEATURE] If '-' is specified as the argument,
state files are disabled.
MODEL and SERIAL are build from drive identify information, invalid characters are replaced by underline.
If the PREFIX has the form '/path/dir/' (e.g. '/var/lib/smartd/'), then files 'MODEL-SERIAL.ata.state' are created in directory '/path/dir'. If the PREFIX has the form '/path/name' (e.g. '/var/lib/misc/smartd-'), then files 'nameMODEL-SERIAL.ata.state' are created in directory '/path/'. The path must be absolute, except if debug mode is enabled.
The state information files are read on smartd startup. The files are always (re)written after reading the configuration file, before rereading the configuration file (SIGHUP), before smartd shutdown, and after a check forced by SIGUSR1. After a normal check cycle, a file is only rewritten if an important change (which usually results in a SYSLOG output) occurred.
If a warning occurs, a child process is created with fork(2). This process closes all inherited file descriptors, connects stdio to /dev/null, changes the user and group ids, removes any supplementary group ids and then calls the popen(3) function from the standard library.
If '0:0' is specified, user and group are not changed, but the remaining actions still apply.
If '-' is specified, popen(3) is called directly. This is the default.
smartd
Runs the daemon in forked mode. This is the normal way to run smartd.
Entries are logged to SYSLOG.
smartd -d -i 30
Run in foreground (debug) mode, checking the disk status every 30 seconds.
smartd -q onecheck
Registers devices, and checks the status of the devices exactly once. The exit
status (the shell $? variable) will be zero if all went well, and
nonzero if no devices were detected or some other problem was
encountered.
The syntax of the smartd.conf(5) file is discussed separately.
smartd will make log entries at loglevel LOG_INFO if
the Normalized SMART Attribute values have changed, as reported using the
'-t', '-p', or '-u' Directives. For example:
'Device: /dev/sda, SMART Attribute: 194 Temperature_Celsius changed from 94
to 93'
Note that in this message, the value given is the 'Normalized' not the 'Raw'
Attribute value (the disk temperature in this case is about 22 Celsius). The
'-R' and '-r' Directives modify this behavior, so that the
information is printed with the Raw values as well, for example:
'Device: /dev/sda, SMART Attribute: 194 Temperature_Celsius changed from 94
[Raw 22] to 93 [Raw 23]'
Here the Raw values are the actual disk temperatures in Celsius. The way in
which the Raw values are printed, and the names under which the Attributes
are reported, is governed by the various '-v Num,Description'
Directives described previously.
Please see the smartctl manual page for further explanation of the differences between Normalized and Raw Attribute values.
smartd will make log entries at loglevel LOG_CRIT if
a SMART Attribute has failed, for example:
'Device: /dev/sdc, Failed SMART Attribute: 5 Reallocated_Sector_Ct'
This loglevel is used for reporting enabled by the '-H', -f',
'-l selftest', and '-l error' Directives. Entries
reporting failure of SMART Prefailure Attributes should not be ignored: they
mean that the disk is failing. Use the smartctl utility to
investigate.
When smartd makes log entries, these are time-stamped. The time stamps are in the computer's local time zone, which is generally set using either the environment variable 'TZ' or using a time-zone file such as /etc/localtime. You may wish to change the timezone while smartd is running (for example, if you carry a laptop to a new time-zone and don't reboot it). Due to a bug in the tzset(3) function of many unix standard C libraries, the time-zone stamps of smartd might not change. For some systems, smartd will work around this problem if the time-zone is set using /etc/localtime. The work-around fails if the time-zone is set using the 'TZ' variable (or a file that it points to).
The exit status (return value) of smartd can have the following values:
Bruce Allen (project initiator),
Christian Franke (project manager, Windows port and all sort of
things),
Douglas Gilbert (SCSI subsystem),
Volker Kuhlmann (moderator of support and database mailing list),
Gabriele Pohl (wiki & development team support),
Alex Samorukov (FreeBSD port and more, new Trac wiki).
Many other individuals have made contributions and corrections, see AUTHORS, ChangeLog and repository files.
The first smartmontools code was derived from the smartsuite package, written by Michael Cornwell and Andre Hedrick.
To submit a bug report, create a ticket in smartmontools wiki:
<https://www.smartmontools.org/>.
Alternatively send the info to the smartmontools support mailing list:
<https://listi.jpberlin.de/mailman/listinfo/smartmontools-support>.
smartd.conf(5), smartctl(8).
update-smart-drivedb(8).
systemd.exec(5).
Please see the following web site for more info: <https://www.smartmontools.org/>
An introductory article about smartmontools is Monitoring Hard Disks with SMART, by Bruce Allen, Linux Journal, January 2004, pages 74–77. See <https://www.linuxjournal.com/article/6983>.
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.
The functioning of SMART was originally defined by the SFF-8035i revision 2 and the SFF-8055i revision 1.4 specifications. These are publications 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 <https://www.smartmontools.org/wiki/Links>.
smartmontools-7.3 2022-02-28 r5338
$Id: smartd.8.in 5333 2022-02-26 00:15:22Z dpgilbert $
| 2022-02-28 | smartmontools-7.3 |