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

NAME

       reiserfstune

SYNOPSIS

       reiserfstune [ -f ] [ -j | --journal-device FILE ] [ --no-journal-available ] [ --journal-new-device FILE ] [ -s | --journal-new-size N ] [
       -o | --journal-new-offset N ] [ -t | --max-transaction-size N ] [ -u | --uuid UUID ] [ -l | --label LABEL ] device

DESCRIPTION

       reiserfstune is used for tuning the ReiserFS journal. It can change two parameters (journal size and maximum transaction size), and it  can
       move  the  journal's  location  to a new specified block device. (The old ReiserFS's journal may be kept unused, or discarded at the user's
       option.)  Note: At the time of writing this feature was implemented for a special release of ReiserFS, and was not expected to be put  into
       the  mainstream kernel until approximately Linux 2.5.  This means that if you have the stock kernel you must apply a special patch. Without
       this patch the kernel will refuse to mount the newly modified file system.  We will charge $25 to explain this to you if you ask us why	it
       doesn't work.

       Perhaps the most interesting application of this code is to put the journal on a solid state disk.

       device is  the  special	file  corresponding to the newly specified block device (e.g /dev/hdXX for IDE disk partition or /dev/sdXX for the
	      SCSI disk partition).

OPTIONS

       -j | --journal-device FILE
	      FILE is the file name of the block device the file system has the current journal (the one prior to running reiserfstune)  on.  This
	      option is required when the journal is already on a separate device from the main data device (although it can be avoided with --no-
	      journal-available). If you don't specify journal device by this option, reiserfstune suppose that journal is on main device.

       --no-journal-available
	      allows reiserfstune to continue when the current journal's block device is no longer available.  This might happen if  a	disk  goes
	      bad and you remove it (and run fsck).

       --journal-new-device FILE
	      FILE  is	the file name of the block device which will contain the new journal for the file system. If you don't specify this, reis-
	      erfstune supposes that journal device remains the same.

	-s | --journal-new-size N
	      N is the size parameter for the new journal. When journal is to be on a separate device - its size defaults to number of blocks that
	      device  has. When journal is to be on the same device as the filesytem - its size defaults to amount of blocks allocated for journal
	      by mkreiserfs when it created the filesystem. Minimum is 513 for both cases.

	-o | --journal-new-offset N
	      N is an offset in blocks where journal will starts from when journal is to be on a separate device. Default is 0. Has no effect when
	      journal  is  to be on the same device as the filesystem.	Most users have no need to use this feature.  It can be used when you want
	      the journals from multiple filesystems to reside on the same device, and you don't want to or cannot partition that device.

	-t | --maximal-transaction-size N
	       is the maximum transaction size parameter for the new journal. The default, and max possible, value is 1024 blocks.  It	should	be
	      less than half the size of the journal. If specifed incorrectly, it will be adjusted.

       -f | --force
	      Normally reiserfstune will refuse to change a journal of a file system that was created before this journal relocation code. This is
	      because if you change the journal, you cannot go back (without special option --make-journal-standard) to an old kernel  that  lacks
	      this  feature and be able to use your filesytem.	This option forces it to do that. Specified more than once it allows to avoid ask-
	      ing for confirmation.

       --make-journal-standard
	      As it was mentioned above, if your file system has non-standard journal, it can not be mounted on the kernel without journal reloca-
	      tion  code.  The thing can be changed, the only condition is that there is reserved area on main device of the standard journal size
	      8193 blocks  (it will be so for instance if you convert standard journal to non-standard). Just specify this option when	you  relo-
	      cate journal back, or without relocation if you already have it on main device.

       -u | --uuid UUID
	      Set   the   universally  unique  identifier ( UUID ) of the filesystem to UUID (see also uuidgen(8)). The  format  of  the  UUID	is
	      a series	of  hex  digits  separated  by	hypthens,  like  this: "c1b9d5a2-f162-11cf-9ece-0020afc76f16".

       -l | --label LABEL
	      Set  the	volume	label  of  the filesystem. LABEL can be at most 16 characters long; if it is longer than 16 characters,  reiserfs-
	      tune will truncate it.

POSSIBLE SCENARIOS OF USING REISERFSTUNE
:
       1. You have ReiserFS on /dev/hda1, and you wish to have it working with its journal on the device /dev/journal

	      boot kernel patched with special "relocatable journal support" patch
	      reiserfstune /dev/hda1 --journal-new-device /dev/journal -f
	      mount /dev/hda1 and use.
	      You would like to change max transaction size to 512 blocks
	      reiserfstune -t 512 /dev/hda1
	      You would like to use your file system on another kernel that doesn't
	      contain relocatable journal support.
	      umount /dev/hda1
	      reiserfstune /dev/hda1 -j /dev/journal --journal-new-device /dev/hda1 --make-journal-standard
	      mount /dev/hda1 and use.

       2. You would like to have ReiserFS on /dev/hda1 and to be able to
       switch between different journals including journal located on the
       device containing the filesystem.

	      boot kernel patched with special "relocatable journal support" patch
	      mkreiserfs /dev/hda1
	      you got solid state disk (perhaps /dev/sda, they typically look like scsi disks)
	      reiserfstune --journal-new-device /dev/sda1 -f /dev/hda1
	      Your scsi device dies, it is three in the morning, you have an extra IDE device
	      lying around
	      reiserfsck --no-journal-available /dev/hda1
	      or
	      reiserfsck --rebuild-tree --no-journal-available /dev/hda1
	      reiserfstune --no-journal-available --journal-new-device /dev/hda1 /dev/hda1
	      using /dev/hda1 under patched kernel

AUTHOR

       This version of reiserfstune has been written by Vladimir Demidov <vova@namesys.com> and Edward Shishkin <edward@namesys.com>.

BUGS

       Please repoort bugs to the ReiserFS mail list <reiserfs-list@namesys.com>

SEE ALSO

       reiserfsck(8), debugreiserfs(8), mkreiserfs(8)

Reiserfsprogs-3.6.4						   January 2002 						   REISERFSTUNE(8)