HDDTEMP(8)HDDTEMP(8)NAMEhddtemp - Utility to monitor hard drive temperature
SYNOPSIShddtemp [options] [type:]disk...
DESCRIPTIONhddtemp will give you the temperature of your hard drive by reading
Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.) infor‐
mation on drives that support this feature. Only modern hard drives
have a temperature sensor. hddtemp supports reading S.M.A.R.T. infor‐
mation from SCSI drives too. hddtemp can work as simple command line
tool or as a daemon.
You can specify one or more device drive path, where each path can be
prefixed with a type like PATA, SATA or SCSI to force hddtemp too use
one of these type (because detection can fail).
The program follows the usual GNU command line syntax, with long
options starting with two dashes (`-'). A summary of options is
Display the database file that allows hddtemp to recognize a
Display various S.M.A.R.T. fields and their values. Useful for
finding a value that seems to match the temperature and/or to
send a report. (done for every drive supplied)
Execute hddtemp in TCP/IP daemon mode (port 7634 by default).
Specify the database file to use.
Don't fork into the background even in daemon mode. This is
useful when running under a process supervisor.
Listen on a specific address. addr is a string containing a
host name or a numeric host address string. The numeric host
address string is a dotted-decimal IPv4 address or an IPv6 hex
Print only the temperature (without the unit).
Port number to listen to (in TCP/IP daemon mode).
Separator to use between fields (in TCP/IP daemon mode). The
default separator is `|'.
Switch to daemon mode and log temperatures to syslog every s
Don't check if the drive is supported.
Force output temperature either in Celsius or Fahrenheit.
Display hddtemp version number.
Wake-up the drive if needed (ATA drives only).
-4 Listen on IPv4 sockets only.
-6 Listen on IPv6 sockets only.
If you know your drive has a temperature sensor but it is being
reported unsupported, tell me which model and which manufacturer it is,
and/or just add a new entry in /etc/hddtemp.db. Each line of
hddtemp.db is either a comment, a blank line or a line containing:
- a regular expression that allow hddtemp to recognize a drive or a
set of drives from its model name or from a generic model name,
- a value (ATTRIBUTE_ID from S.M.A.R.T.),
- a C or an F to set the unit to Celsius or Fahrenheit,
- a description.
Feedback is welcome (see the REPORT section below).
TCP/IP DAEMON MODE
Example of type forcing:
# hddtemp SATA:/dev/sda PATA:/dev/hda
To test hddtemp in daemon mode, start it like this:
# hddtemp-d /dev/hd[abcd]
and use telnet or netcat (which is known as nc on some systems) to get
# netcat localhost 7634
The drive database is read only once at startup, so hddtemp must be
restarted if the database is updated for the changes to take effect.
As I receive a lot of reports, things must be clarified. When running
hddtemp with debug options, hddtemp will show sort of a dump of
S.M.A.R.T. data. Each field corresponds to an information field. The
standard field for drive temperature is 194. But this is not always
the case (mostly for older drives). Even if your drive has S.M.A.R.T.
capabilities, it doesn't necessarily mean that it can report its tem‐
perature. So, things must be determined through experimentation.
So, you can try to guess which field by is the good one by running
hddtemp at regular intervals:
- just after starting up your PC/server/station,
- after opening a window (a physical window :),
- after opening the case,
- whatever you can think of...
and looking for a field's value that would increase or decrease depend‐
ing on what effect you want to induce. Be careful, fields 4, 9, and 12
are often reported to match a temperature field but after some investi‐
gation they do not. But fields 194 (which is the standard field for
temperature) and 231 are good candidates.
Then, you can send me a report with outputs from `hddtemp --debug ...',
`smartctl' or `hdparm -i ...', and/or add an entry in hddtemp.db your‐
If hddtemp crashes (yes, it might) for some unknown reasons, look for a
file named hddtemp.backtrace.<PID>.XXXXXX (where XXXXXX is a random
number generated at runtime) in /tmp. Then, you can then send me this
file and the hddtemp binary. The backtrace functionality is currently
supported on i386 architectures only.
SEE ALSOsmartctl(8), syslog(3), syslogd(8).
Emmanuel Varagnat (email@example.com).
This manual page was originally written by Aurelien Jarno
<firstname.lastname@example.org>, for the Debian GNU/Linux system (but may be used
July 21, 2003 HDDTEMP(8)