HDDTEMP(8)                           System Manager's Manual                           HDDTEMP(8)



NAME
       hddtemp - Utility to monitor hard drive temperature

SYNOPSIS
       hddtemp [options] [type:]disk...

DESCRIPTION
       hddtemp will give you the temperature of your hard drive by reading Self-Monitoring Analy‐
       sis and Reporting Technology (S.M.A.R.T.)  information on drives that  support  this  fea‐
       ture.   Only  modern  hard  drives  have  a  temperature sensor.  hddtemp supports reading
       S.M.A.R.T.  information 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).



OPTIONS
       The program follows the usual GNU command line syntax, with long options starting with two
       dashes (`-').  A summary of options is included below.

       -b, --drivebase
              Display the database file that allows hddtemp to recognize a supported drive.

       -D, --debug
              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)

       -d, --daemon
              Execute hddtemp in TCP/IP daemon mode (port 7634 by default).

       -f, --file=file
              Specify the database file to use.

       -F, --foreground
              Don't fork into the background even in daemon mode.  This is  useful  when  running
              under a process supervisor.

       -l, --listen=addr
              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 address.

       -n, --numeric
              Print only the temperature (without the unit).

       -p, --port=#
              Port number to listen to (in TCP/IP daemon mode).

       -s, --separator=char
              Separator  to use between fields (in TCP/IP daemon mode).  The default separator is
              `|'.

       -S, --syslog=s
              Switch to daemon mode and log temperatures to syslog every s seconds.

       -q, --quiet
              Don't check if the drive is supported.

       -u, --unit=C|F
              Force output temperature either in Celsius or Fahrenheit.

       -v, --version
              Display hddtemp version number.

       -w, --wake-up
              Wake-up the drive if needed (ATA drives only).

       -4     Listen on IPv4 sockets only.

       -6     Listen on IPv6 sockets only.



DRIVE DATABASE
       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 con‐
       taining:

       - 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 a reply:

       # netcat localhost 7634

       The drive database is read only once at startup, so hddtemp must be restarted if the data‐
       base is updated for the changes to take effect.


REPORT
       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. capabili‐
       ties, it doesn't necessarily mean that it can report its temperature.  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 depending on  what  effect
       you want to induce.  Be careful, fields 4, 9, and 12 are often reported to match a temper‐
       ature field but after some investigation they do not.  But fields 194 (which is the  stan‐
       dard 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 yourself.


BUGS
       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  func‐
       tionality is currently supported on i386 architectures only.


SEE ALSO
       smartctl(8), syslog(3), syslogd(8).


AUTHOR
       Emmanuel Varagnat (hddtemp AT guzu.net).

       This  manual  page  was originally written by Aurelien Jarno <aurel32 AT debian.org>, for the
       Debian GNU/Linux system (but may be used by others).



                                          July 21, 2003                                HDDTEMP(8)