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mhddfs(1)		    General Commands Manual		     mhddfs(1)

NAME
       mhddfs  -  The  driver  combines	a several mount	points into the	single
       one.

SYNOPSIS
	mhddfs /dir1,/dir2[,/path/to/dir3] /path/to/mount [-o options]
	mhddfs /dir1 dir2,dir3 /mount/point [-o	options]
	...
	fusermount -u /path/to/mount

   fstab record	example:
       mhddfs#/path/to/dir1,/path/to/dir2 /mnt/point fuse defaults 0 0

       mhddfs#/dir1,/dir2,/dir3	/mnt fuse logfile=/var/log/mhddfs.log 0	0

OPTIONS
       with an -o option1,option2...  you can specify some additional options:

   logfile=/path/to/file.log
       specify a file that will	contain	debug information.

   loglevel=x
       0 - debug messages

       1 - info	messages

       2 - standard (default) messages

   mlimit=size[m|k|g]
       a free space size threshold If a	drive has the free space less than the
       threshold  specifed then	another	drive will be choosen while creating a
       new file.  If all the drives have free space less  than	the  threshold
       specified then a	drive containing most free space will be choosen.

       Default value is	4G, minimum value is 100M.

       This option accepts suffixes:
	      [mM] - megabytes

	      [gG] - gigabytes

	      [kK] - kilobytes

       For an information about	the additional options see output of:
	      mhddfs -h

DESCRIPTION
       The file	system allows to unite a several mount points (or directories)
       to the single one. So a one big filesystem is simulated and this	 makes
       it  possible  to	combine	a several hard drives or network file systems.
       This system is like unionfs but it can choose a drive with the most  of
       free  space, and	move the data between drives transparently for the ap-
       plications.

       While writing files they	are written to a 1st hdd until the hdd has the
       free  space  (see  mlimit  option), then	they are written on a 2nd hdd,
       then to 3rd etc.

       df will show a total statistics of all filesystems like there is	a  big
       one hdd.

       If an overflow arises while writing to the hdd1 then a file content al-
       ready written will be transferred to a hdd containing  enough  of  free
       space  for  a  file.  The  transferring	is processed on-the-fly, fully
       transparent for the application that is writing.	So this	behaviour sim-
       ulates a	big file system.

   WARNINGS
       The  filesystems	 are  combined must provide a possibility to get their
       parameters correctly (e.g. size of free space). Otherwise  the  writing
       failure can occur (but data consistency will be ok anyway). For example
       it is a bad idea	to combine a several sshfs systems together.

       Please read FUSE	documentation for a further conception.

COPYRIGHT
       Distributed under GPLv3

       Copyright (C) 2008 Dmitry E. Oboukhov _dimka@avanto.org_

				 February 2008			     mhddfs(1)

NAME | SYNOPSIS | OPTIONS | DESCRIPTION | COPYRIGHT

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