NAME

       hd-idle - spin down idle hard disks

SYNOPSIS

       hd-idle [options]

DESCRIPTION

       hd-idle  is  a  utility  program for spinning down external disks after a period of idle time. Since most
       external IDE disk enclosures don't support setting the IDE idle timer, a program like hd-idle is required
       to spin down idle disks automatically.

       A word of caution: hard disks don't like spinning up too often. Laptop disks  are  more  robust  in  this
       respect  than desktop disks but if you set your disks to spin down after a few seconds you may damage the
       disk over time due to the stress the spin-up causes on the spindle motor  and  bearings.  It  seems  that
       manufacturers recommend a minimum idle time of 3-5 minutes, the default in hd-idle is 10 minutes.

OPTIONS

       -a name
              Set  device name of disks for subsequent idle-time parameters (-i).  This parameter is optional in
              the sense that there's a default entry for all disks which are not named otherwise by  using  this
              parameter. This can also be a symlink (e.g. /dev/disk/by-uuid/...)

       -i idle_time
              Idle  time  in seconds for the currently named disk(s) (-a <name>) or for all disks.  Setting this
              value to "0" will never spin down the disk(s).

       -c command_type
              Api call to stop the device. Possible values are "scsi" (default value) and "ata".

       -p power_condition
              Power condition to send with the issued SCSI START STOP UNIT command.  Possible values are  "0-15"
              (inclusive).  The  default  value  of "0" works fine for disks accessible via the SCSI layer (USB,
              IEEE1394, ...), but it will *NOT* work as intended with real SCSI / SAS disks. A stopped SAS  disk
              will not start up automatically on access, but requires a startup command for reactivation. Useful
              values for  SAS disks are "2" for idle and "3" for standby.

       -s symlink_policy
              Set the policy to resolve symlinks for devices. If set to "0", symlinks are resolve only on start.
              If  set  to "1", symlinks are also resolved on runtime until success. By default symlinks are only
              resolve on start.  If the symlink doesn't resolve to a device, the default configuration  will  be
              applied.

       -l logfile
              Name  of logfile (written only after a disk has spun up). Please note that this option might cause
              the disk which holds the logfile to spin up just because another  disk  had  some  activity.  This
              option  should  not  be  used  on  systems  with more than one disk except for tuning purposes. On
              single-disk systems, this option should not cause any additional spinups.

       -t disk
              Spin-down the specified disk immediately and exit. It can  be  used  in  combination  with  -c  to
              specify the command type.

       -d     Debug  mode.  It  will  print  debugging info to stdout/stderr (/var/log/syslog if started as with
              systemctl)

       -h     Print usage information.

DISK SELECTION

       The parameter -a can be used to set a filter on the disk's device name (omit /dev/) for subsequent  idle-
       time settings. The default is all disks:

       1)     A -i option before the first -a option will set the default idle time.

       2)     In  order  to  disable  spin-down  of  disks per default, and then re-enable spin-down on selected
              disks, set the default idle time to 0.

EXAMPLE

       hd-idle -i 0 -a sda -i 300 -a sdb -i 1200

       This example sets the default idle time to 0 (meaning hd-idle will never try to spin  down  a  disk)  and
       default  "scsi" api command, then sets explicit idle times for disks which have the string "sda" or "sdb"
       in their device name.

EXAMPLE

       hd-idle -i 0 -c ata -a sda -i 300 -a sdb -i 1200 -c scsi

       This example sets the default idle time to 0 (meaning hd-idle will never try to spin  down  a  disk)  and
       default  "ata"  api command, then sets explicit idle times for disks which have the string "sda" or "sdb"
       in their device name and sets "sdb" to use "ata" api command.

       The option -c allows to set the api call that sends the spindown command.   Possible  values  are  "scsi"
       (the default value) or "ata".

AUTHOR

       hd-idle   was   written   by   Andoni   del  Olmo  <andoni.delolmo@gmail>  based  on  Chistian  Mueller's
       <chris@mumac.de> work.

       This manual page was written by Christian Mueller <chris@mumac.de>, for the Debian project  (and  may  be
       used by others).

       Modified by Andoni del Olmo <andoni.delolmo@gmail.com>.

                                                September 8, 2019                                     HD-IDLE(8)