Provided by: sg3-utils_1.33-1_amd64 bug

NAME

       sg_start - send SCSI START STOP UNIT command to start, stop, load or eject medium

SYNOPSIS

       sg_start  [0]  [1] [--eject] [--help] [--fl=FL] [--immed] [--load] [--loej] [--mod=PC_MOD]
       [--noflush] [--pc=PC] [--readonly] [--start] [--stop] [--verbose] [--version] DEVICE

       sg_start [--eject] [--fl=FL] [-i] [--imm=0|1] [--load] [--loej] [--mod=PC_MOD] [--noflush]
       [--pc=PC] [-r] [--start] [--stop] [-v] [-V] [0|1] DEVICE

DESCRIPTION

       sg_start sends a SCSI START STOP UNIT command to the DEVICE with the selected options. The
       most used options are --stop to spin down a disk and --start to  spin  up  a  disk.  Using
       --start  on a disk that is already spinning is harmless. There is also finer grain control
       with "power condition": active, idle or standby. This is set with the --pc=PC  option.  In
       some contexts the "stop" state can be considered an additional power condition.

       Devices that contain removable media such as cd/dvds can use the --loej option to load the
       medium  when  used  in  conjunction  with  --start  (i.e.  load  medium  then  spin   up).
       Alternatively  --loej may be used to eject the medium when used in conjunction with --stop
       (i.e. spin down then eject medium). More simply, the loading or ejecting  of  a  removable
       medium can be requested with the --load or --eject' option.

       If  no  option  or  argument  is  given  then  a --start is assumed; as the utility's name
       suggests.

       This utility supports two command line syntaxes, the preferred one is shown first  in  the
       synopsis  and  explained  in  this section. A later section on the old command line syntax
       outlines the second group of options.

OPTIONS

       Arguments to long options are mandatory for short options as well.

       0      same action as --stop.

       1      same action as --start.

       -e, --eject
              stop the medium and eject it from the drive. Only appropriate  for  a  device  with
              removable medium. Might be ignored (prevented), see below.

       -h, --help
              print out the usage message then exit.

       -f, --fl=FL
              sets  the format layer number for the disc to "jump" to (defined in MMC-5).  Values
              of FL can be 0 to 3. When this option is chosen, the FL, LoEj and  Start  bits  are
              set in the cdb as required by MMC-5; thus the user does not need to set the --start
              and/or --load options.

       -i, --immed
              sets the IMM bit on the START  STOP  UNIT  command  so  this  utility  will  return
              immediately  and  not  wait  for  the  media  to complete the requested action. The
              default is to wait  until  the  media  to  complete  the  requested  action  before
              returning.

       -l, --load
              load the medium in the drive and start it. Only appropriate for a removable medium.

       -L, --loej
              sets  the  LOEJ  bit  on the START STOP UNIT command. This loads the media when the
              unit is started or eject it when the unit is stopped (i.e.   works  in  conjunction
              with  START  bit in cdb). This option is ignored if 'pc > 0'.  Default is off (i.e.
              don't attempt to load or eject media). If a start/start  indication  is  not  given
              (i.e.  neither  --start  nor --stop) and this option is given then a load and start
              action is assumed.

       -m, --mod=PC_MOD
              where PC_MOD is the 'power condition modifier' value. 0 to 15 (inclusive) are valid
              and  0  is the default. This  'power condition modifier' field in the cdb was added
              after sbc3r13.

       -n, --noflush
              do not perform a flush to media (e.g. like SYNCHRONIZE CACHE does) before a variant
              of  this  utility  that  limits  access to the media. Using the --stop option is an
              example of something that limits access to the media. This 'noflush' field  in  the
              cdb was added after sbc3r13.

       -O, --old
              switch to older style options.

       -p, --pc=PC
              where  PC  is the 'power conditions' value. 0 to 15 (inclusive) are valid.  Default
              value is 0. When '--pc=0' then --eject, --load,  --loej,  --start  and  --stop  are
              active.  Some common values are 1 for the "active" power condition (SBC); 2 for the
              idle power condition; 3  for  the  standby  power  condition;  5  for  sleep  power
              condition  (MMC);  7  for LU_CONTROL (SBC), 0xa (decimal 10) for FORCE_IDLE_0 (SBC)
              and 0xb (decimal 11) for FORCE_STANDBY_0 (SBC). See recent  SBC-3,  MMC-5  and  SAS
              drafts at www.t10.org for more information.

       -r, --readonly
              open  the  DEVICE  in  read-only  mode.  Maybe required in Linux to stop a nuisance
              spin-up if the DEVICE is an ATA disk. The nuisance spin-up may occur at the end  of
              this command negating the effect of the --stop option.

       -s, --start
              start  (spin-up)  the DEVICE. This sets the START bit in the cdb. Using this option
              on an already started device is harmless. In the absence  of  other  options,  this
              option defaults (i.e. set the START cdb bit).

       -S, --stop
              stop (spin-down) the DEVICE. This clears the START bit in the cdb.

       -v, --verbose
              increase the level of verbosity. Can be used multiple times.

       -V, --version
              print out version string then exit.

NOTES

       To avoid confusion, only one of 0, 1 --eject, --load, --start and --stop should be given.

       There is an associated "power condition" mode page (0x1a) in which timer values can be set
       for transitioning to either idle or standby state after a period of inactivity. The sdparm
       utility  can be used to view the power condition mode page and if required change it. If a
       DEVICE is in either idle or standby power condition state then  a  REQUEST  SENSE  command
       (see  the  sg_requests  utility)  should yield a sense key of "no sense" and an additional
       sense code of "Low power condition on" on recent SCSI devices.

       Ejection of removable media (e.g. 'sg_start --eject /dev/hdd' where the DEVICE is an ATAPI
       cd/dvd  drive)  may be prevented by a prior SCSI PREVENT ALLOW MEDIUM REMOVAL command (see
       sg_prevent). In this case this utility should fail with an error generated by the  device:
       illegal  request  /  medium removal prevented. This can be overridden using sg_prevent or,
       for example, 'sdparm --command=unlock /dev/hdd'.

       The SCSI TEST UNIT READY command can be used to find out whether  a  DEVICE  is  ready  to
       transfer  data.  If  rotating  media is stopped or still coming up to speed, then the TEST
       UNIT READY command will yield a "not ready" sense key and an more  informative  additional
       sense code. See the sg_turs utility.

       In  the  2.4 series of Linux kernels the DEVICE must be a SCSI generic (sg) device. In the
       2.6 series block devices (e.g. SCSI disks and DVD  drives)  can  also  be  specified.  For
       example "sg_start 0 /dev/sda" will work in the 2.6 series kernels.

       In the Linux 2.6 series, especially with ATA disks, using this utility to stop (spin down)
       a disk may not be sufficient and other mechanisms will start  the  disk  again  some  time
       later.  The  user  might  additionally  mark  the  disk  as "offline" with 'echo offline >
       /sys/block/sda/device/state' where sda is the block name of the disk. To restart the  disk
       "offline" can be replaced with "running". Note that once the 'state' is set to offline, no
       SCSI commands can be sent to the device until it is set back to running. Also  stopping  a
       disk  via a pass-through interface (e.g. /dev/sg1 or /dev/bsg/1:0:0:0) may reduce unwanted
       side effects (such as restarting it again when this utility completes).

EXIT STATUS

       The exit status of sg_start is 0 when it is successful. Otherwise see the sg3_utils(8) man
       page.

OLDER COMMAND LINE OPTIONS

       The options in this section were the only ones available prior to sg3_utils version 1.23 .
       In sg3_utils version 1.23 and later these older options can be selected by either  setting
       the SG3_UTILS_OLD_OPTS environment variable or using '--old' (or '-O) as the first option.

       Note  that the action of --loej is slightly different in the older interface: when neither
       --start nor --stop (nor proxies for them) are given, --loej performs an  eject  operation.
       In the same situation the newer interface will perform a load operation.

       Earlier  versions  of  sg_start  had  a '-s' option to perform a SYNCHRONIZE CACHE command
       before the START STOP UNIT command was issued. According to recent SBC-2  drafts  this  is
       done implicitly if required. Hence the '-s' option has been dropped.

       All  options,  other  than  '-v'  and  '-V', can be given with a single "-".  For example:
       "sg_start -stop /dev/sda" and "sg_start --stop /dev/sda" are equivalent.  The  single  "-"
       form is for backward compatibility.

       0      stop (spin-down) DEVICE.

       1      start (spin-up) DEVICE.

       --eject
              stop the medium and eject it from the drive.

       --fl=FL
              sets the format layer number for the disc to "jump" to (defined in MMC-5).

       -i     sets  the  IMM  bit  on  the  START  STOP  UNIT command so this utility will return
              immediately and not wait for the media to spin down. Same effect as '--imm=1'.  The
              default  action  (without  this  option or a '--imm=1' option) is to wait until the
              media spins down before returning.

       --imm=0|1
              when the immediate bit is 1 then this utility returns immediately after the  DEVICE
              has  received  the  command.  When  this option is 0 (the default) then the utility
              returns once the command has completed its action (i.e. it waits until  the  device
              is started or stopped).

       --load load the medium in the drive and start it.

       --loej sets  the  LOEJ  bit  in  the  START  STOP  UNIT  cdb.  When a "start" operation is
              indicated, then a  load  and  start  is  performed.  When  a  "stop"  operation  is
              indicated,  then  a  stop  and eject is performed. When neither a "start" or "stop"
              operation is indicated does a stop and eject. [Note that the  last  action  differs
              from  the  new  interface  in  which  the  option of this name defaults to load and
              start.]

       -N     switch to the newer style options.

       --mod=PC_MOD
              where PC_MOD is the 'power condition modifier' value. 0 to 15 (inclusive) are valid
              and 0 is the default. This field was added after sbc3r13.

       --noflush
              do not perform a flush to media (e.g. like SYNCHRONIZE CACHE does) before a variant
              of this utility that limits access to the media. Using  the  --stop  option  is  an
              example  of  something  that limits access to the media. This field was added after
              sbc3r13.

       --pc=PC
              where PC is the 'power condition' value (in hex). 0 to  f  (inclusive)  are  valid.
              Default value is 0.

       -r     see the --readonly option above. May be useful for ATA disks.

       --start
              start (spin-up) DEVICE.

       --stop stop (spin-down) DEVICE. Same meaning as "0" argument.

       -v     verbose: outputs SCSI command in hex to console before with executing it. '-vv' and
              '-vvv' are also accepted yielding greater verbosity.

       -V     print out version string then exit.

AUTHOR

       Written by K. Garloff and D. Gilbert

REPORTING BUGS

       Report bugs to <dgilbert at interlog dot com>.

COPYRIGHT

       Copyright © 2002-2011 Kurt Garloff, Douglas Gilbert
       This software is distributed under the GPL version 2. There is NO warranty; not  even  for
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

SEE ALSO

       sg_prevent(sg3_utils), sg_requests(sg3_utils), sg_turs(sg3_utils) sdparm(sdparm)