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Revise the markup and apply some wordsmithing.

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Reviewed by:	pjd
MFC after:	3 days
This commit is contained in:
Ruslan Ermilov 2007-11-15 06:23:33 +00:00
parent 4b9322aee8
commit 5419612785
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=173623
1 changed files with 27 additions and 24 deletions
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51
sbin/geom/class/journal/gjournal.8
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@ -24,7 +24,7 @@
.\" .\"
.\" $FreeBSD$ .\" $FreeBSD$
.\" .\"
.Dd December 5, 2006 .Dd November 14, 2007
.Dt GJOURNAL 8 .Dt GJOURNAL 8
.Os .Os
.Sh NAME .Sh NAME
@ -66,31 +66,31 @@ utility is used for journal configuration on the given GEOM provider.
The Journal and data may be stored on the same provider or on two separate The Journal and data may be stored on the same provider or on two separate
providers. providers.
This is block level journaling, not file system level journaling, which means This is block level journaling, not file system level journaling, which means
.Nm everything gets logged, e.g.\& for file systems, it journals both data and
everything gets logged, e.g.: for file systems, it journals both data and
metadata. metadata.
The The
.Nm .Nm
GEOM class can talk to file systems, which allows the use of GEOM class can talk to file systems, which allows the use of
.Nm .Nm
for file system journaling and to keep file systems in a consistent state. for file system journaling and to keep file systems in a consistent state.
At this time, only UFS file systems are supported. At this time, only UFS file system is supported.
.Pp .Pp
.\" XXX This next sentence needs fixed, it's a run on. To configure journaling on the UFS file system using
To configure journaling via .Nm ,
one should first create a
.Nm .Nm
for the UFS file system, one should create a gjournaled provider using the provider using the
.Nm .Nm
utility with the utility, then run
.Fl J
flag for
.Xr newfs 8 .Xr newfs 8
or or
.Xr tunefs 8 .Xr tunefs 8
which instructs UFS to cooperate with the on it with the
.Fl J
flag which instructs UFS to cooperate with the
.Nm .Nm
provider below. provider below.
There are important differences in how gjournaled UFS works. There are important differences in how journaled UFS works.
The most important one is that The most important one is that
.Xr sync 2 .Xr sync 2
and and
@ -111,17 +111,17 @@ option.
When When
.Nm .Nm
is configured on top of is configured on top of
.Nm gmirror .Xr gmirror 8
or or
.Nm graid3 .Xr graid3 8
providers, it also keeps them in a consistent state, thus providers, it also keeps them in a consistent state, thus
automatic synchronization on power failure or system crash may be disabled automatic synchronization on power failure or system crash may be disabled
on those providers. on those providers.
.Pp .Pp
The The
.Nm .Nm
utility uses on-disk metadata, stored in the provider's last sector, to store all needed utility uses on-disk metadata, stored in the provider's last sector,
information. to store all needed information.
This could be a problem when an existing file system is converted to use This could be a problem when an existing file system is converted to use
.Nm . .Nm .
.Pp .Pp
@ -133,7 +133,7 @@ indicates an action to be performed:
Configures Configures
.Nm .Nm
on the given provider(s). on the given provider(s).
If only one provider is given, both data and journal is stored on the same If only one provider is given, both data and journal are stored on the same
provider. provider.
If two providers are given, the first one will be used as data provider and the If two providers are given, the first one will be used as data provider and the
second will be used as the journal provider. second will be used as the journal provider.
@ -143,8 +143,8 @@ Additional options include:
.It Fl f .It Fl f
May be used to convert an existing file system to use May be used to convert an existing file system to use
.Nm , .Nm ,
but only if the journal will be configured on a separate provider and if the last but only if the journal will be configured on a separate provider and if the
sector in the data provider is not used by the existing file system. last sector in the data provider is not used by the existing file system.
If If
.Nm .Nm
detects that the last sector is used, it will refuse to overwrite it detects that the last sector is used, it will refuse to overwrite it
@ -155,7 +155,7 @@ flag, which will force
.Nm .Nm
to overwrite the last sector. to overwrite the last sector.
.It Fl h .It Fl h
Hardcode provider names in meta-data. Hardcode provider names in metadata.
.It Fl s Ar jsize .It Fl s Ar jsize
Specifies size of the journal if only one provider is used for both data and Specifies size of the journal if only one provider is used for both data and
journal. journal.
@ -166,7 +166,7 @@ It is not recommended to use
for small file systems (e.g.: only few gigabytes big). for small file systems (e.g.: only few gigabytes big).
.El .El
.It Cm clear .It Cm clear
Clear meta-data on the given providers. Clear metadata on the given providers.
.It Cm stop .It Cm stop
Stop the given provider. Stop the given provider.
.Pp .Pp
@ -211,12 +211,15 @@ newfs -J /dev/da0.journal
mount -o async /dev/da0.journal /mnt mount -o async /dev/da0.journal /mnt
.Ed .Ed
.Pp .Pp
Configure gjournaling on an existing file system, but only if Configure journaling on an existing file system, but only if
.Nm .Nm
allows this (i.e.: if the last sector is not already used by the file system): allows this (i.e., if the last sector is not already used by the file system):
.Bd -literal -offset indent .Bd -literal -offset indent
umount /dev/da0s1d umount /dev/da0s1d
gjournal label da0s1d da0s1e && tunefs -J enable -n disable && mount -o async /dev/da0s1d.journal /mnt || mount /dev/da0s1d /mnt gjournal label da0s1d da0s1e && \e
tunefs -J enable -n disable && \e
mount -o async /dev/da0s1d.journal /mnt || \e
mount /dev/da0s1d /mnt
.Ed .Ed
.Sh SEE ALSO .Sh SEE ALSO
.Xr geom 4 , .Xr geom 4 ,