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Updated: July 2014

sg_sync (1m)


sg_sync - send the scsi command synchronize cache


sg_sync  [--count=COUNT]  [--group=GROUP] [--help] [--immed]
[--lba=LBA] [--sync-nv] [--verbose] [--version] DEVICE


SG3_UTILS                                              SG_SYNC(8)

     sg_sync - send the scsi command synchronize cache

     sg_sync  [--count=COUNT]  [--group=GROUP] [--help] [--immed]
     [--lba=LBA] [--sync-nv] [--verbose] [--version] DEVICE

     Send SYNCHRONIZE CACHE (10) command to DEVICE. This  command
     is defined for SCSI block devices (see SBC-2). If successful
     this command makes sure that any blocks  whose  latest  ver-
     sions  are  held  in  (volatile)  cache are written to (also
     termed as "synchronized with") the medium. If the  --sync-nv
     option is given and the device has a non-volatile cache then
     any blocks whose latest versions are held in volatile  cache
     are written to non-volatile cache.

     If  the  LBA  and  COUNT  arguments  are  both  zero  (their
     defaults) then all blocks in the cache are synchronized.  If
     LBA  is greater than zero while COUNT is zero then blocks in
     the cache whose addresses are from and including LBA to  the
     highest  lba on the device are synchronized. If both LBA and
     COUNT are non zero then blocks in the cache whose  addresses
     lie  in  the range LBA to LBA+COUNT-1 inclusive are synchro-
     nized with the medium.

     Arguments to long options are mandatory for short options as

     -c, --count=COUNT
          where COUNT is the number of blocks to synchronize from
          and including LBA. Default value is 0. When 0 then  all
          blocks  in  the (volatile) cache from and including LBA
          argument to the highest block address are synchronized.

     -g, --group=GROUP
          where  GROUP is the group number which can be between 0
          and 31 inclusive.  The default value is 0 . Group  num-
          bers  are  used  to segregate data collected within the
          device. This is a new feature in SBC-2 and can probably
          be ignored for the time being.

     -h, --help
          output the usage message then exit.

     -i, --immed
          sets  the  IMMED  bit in the SYNCHRONIZE CACHE command.
          This instructs the device, if the format of the command
          is  acceptable,  to  return  a  GOOD status immediately
          rather than wait for the blocks in the (volatile) cache
          to  be  synchronized  with (i.e. written to) the medium

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SG3_UTILS                                              SG_SYNC(8)

          (or the non-volatile cache).

     -l, --lba=LBA
          where LBA is the lowest logical block  address  in  the
          (volatile)  cache  to synchronize to the medium (or the
          non-volatile cache). Default value is 0 .

     -s, --sync-nv
          synchronize the (volatile) cache with the  non-volatile
          cache.   Without   this  option  (or  if  there  is  no
          non-volatile cache in the device)  the  synchronization
          is with the medium.

     -v, --verbose
          increase the level of verbosity, (i.e. debug output).

     -V, --version
          print the version string and then exit.

     See   attributes(5)   for   descriptions  of  the  following

     |Availability   | system/storage/sg3_utils |
     |Stability      | Uncommitted              |
     Various numeric arguments (e.g. LBA) may include multiplica-
     tive  suffixes  or be given in hexadecimal. See the "NUMERIC
     ARGUMENTS" section in the sg3_utils(8) man page.

     The exit status of sg_sync is 0 when it is successful.  Oth-
     erwise see the sg3_utils(8) man page.

     Written by Douglas Gilbert.

     Report bugs to <dgilbert at interlog dot com>.

     Copyright (C) 2004-2009 Douglas Gilbert
     This  software is distributed under a FreeBSD license. There
     is NO warranty; not even for MERCHANTABILITY or FITNESS  FOR

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SG3_UTILS                                              SG_SYNC(8)


     This   software   was   built   from   source  available  at   The   original
     community       source       was       downloaded       from

     Further information about this software can be found on  the
     open        source        community        website        at

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