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)