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authorru <ru@FreeBSD.org>2004-07-02 21:45:06 +0000
committerru <ru@FreeBSD.org>2004-07-02 21:45:06 +0000
commit46fddaa54b09baa407fa66a14d46c0cc3a906e60 (patch)
tree602e903272257a1c5b455a48800dcaa680741026 /sbin/ccdconfig/ccdconfig.8
parent20fbd172b22ab587e9d796f4cb8664a235cebe78 (diff)
downloadFreeBSD-src-46fddaa54b09baa407fa66a14d46c0cc3a906e60.zip
FreeBSD-src-46fddaa54b09baa407fa66a14d46c0cc3a906e60.tar.gz
Mechanically kill hard sentence breaks.
Diffstat (limited to 'sbin/ccdconfig/ccdconfig.8')
-rw-r--r--sbin/ccdconfig/ccdconfig.860
1 files changed, 40 insertions, 20 deletions
diff --git a/sbin/ccdconfig/ccdconfig.8 b/sbin/ccdconfig/ccdconfig.8
index fdba97b..ca79dc8 100644
--- a/sbin/ccdconfig/ccdconfig.8
+++ b/sbin/ccdconfig/ccdconfig.8
@@ -62,13 +62,15 @@
The
.Nm
utility is used to dynamically configure and unconfigure concatenated disk
-devices, or ccds. For more information about the ccd, see
+devices, or ccds.
+For more information about the ccd, see
.Xr ccd 4 .
.Pp
The options are as follows:
.Bl -tag -width indent
.It Fl c
-Configure a ccd. This is the default behavior of
+Configure a ccd.
+This is the default behavior of
.Nm .
.It Fl C
Configure all ccd devices listed in the ccd configuration file.
@@ -79,8 +81,10 @@ instead of the default
.Pa /etc/ccd.conf .
.It Fl g
Dump the current ccd configuration in a format suitable for use as the
-ccd configuration file. If no arguments are specified, every configured
-ccd is dumped. Otherwise, the configuration of each listed ccd is dumped.
+ccd configuration file.
+If no arguments are specified, every configured
+ccd is dumped.
+Otherwise, the configuration of each listed ccd is dumped.
.It Fl u
Unconfigure a ccd.
.It Fl U
@@ -93,7 +97,8 @@ to be verbose.
.Pp
A ccd is described on the command line and in the ccd configuration
file by the name of the ccd, the interleave factor, the ccd configuration
-flags, and a list of one or more devices. The flags may be represented
+flags, and a list of one or more devices.
+The flags may be represented
as a decimal number, a hexadecimal number, a comma-separated list
of strings, or the word
.Dq none .
@@ -127,17 +132,22 @@ as shown by
.Sh EXAMPLES
A number of
.Nm
-examples are shown below. The arguments passed
+examples are shown below.
+The arguments passed
to
.Nm
are exactly the same as you might place in the
.Pa /etc/ccd.conf
-configuration file. The first example creates a 4-disk stripe out of
-four scsi disk partitions. The stripe uses a 64 sector interleave.
+configuration file.
+The first example creates a 4-disk stripe out of
+four scsi disk partitions.
+The stripe uses a 64 sector interleave.
The second example is an example of a complex stripe/mirror combination.
It reads as a two disk stripe of da4 and da5 which is mirrored
-to a two disk stripe of da6 and da7. The last example is a simple
-mirror. The 2nd slice of /dev/da8 is mirrored with the 3rd slice of /dev/da9
+to a two disk stripe of da6 and da7.
+The last example is a simple
+mirror.
+The 2nd slice of /dev/da8 is mirrored with the 3rd slice of /dev/da9
and assigned to ccd0.
.Pp
.Bd -unfilled -offset
@@ -150,14 +160,19 @@ When you create a new ccd disk you generally want to
.Xr fdisk 8
and
.Xr disklabel 8
-it before doing anything else. Once you create the initial label you can
-edit it, adding additional partitions. The label itself takes up the first
-16 sectors of the ccd disk. If all you are doing is creating file systems
+it before doing anything else.
+Once you create the initial label you can
+edit it, adding additional partitions.
+The label itself takes up the first
+16 sectors of the ccd disk.
+If all you are doing is creating file systems
with newfs, you do not have to worry about this as newfs will skip the
-label area. However, if you intend to
+label area.
+However, if you intend to
.Xr dd 1
to or from a ccd partition it is usually a good idea to construct the
-partition such that it does not overlap the label area. For example, if
+partition such that it does not overlap the label area.
+For example, if
you have A ccd disk with 10000 sectors you might create a 'd' partition
with offset 16 and size 9984.
.Pp
@@ -173,16 +188,21 @@ the disklabel you
had created before will still be there and not require reinitialization.
Beware that changing any ccd parameters: interleave, flags, or the
device list making up the ccd disk, will usually destroy any prior
-data on that ccd disk. If this occurs it is usually a good idea to
+data on that ccd disk.
+If this occurs it is usually a good idea to
reinitialize the label before [re]constructing your ccd disk.
.Sh RECOVERY
An error on a ccd disk is usually unrecoverable unless you are using the
-mirroring option. But mirroring has its own perils: It assumes that
-both copies of the data at any given sector are the same. This holds true
+mirroring option.
+But mirroring has its own perils: It assumes that
+both copies of the data at any given sector are the same.
+This holds true
until a write error occurs or until you replace either side of the mirror.
-This is a poor-man's mirroring implementation. It works well enough that if
+This is a poor-man's mirroring implementation.
+It works well enough that if
you begin to get disk errors you should be able to backup the ccd disk,
-replace the broken hardware, and then regenerate the ccd disk. If you need
+replace the broken hardware, and then regenerate the ccd disk.
+If you need
more than this you should look into external hardware RAID SCSI boxes,
RAID controllers (see GENERIC),
or software RAID systems such as
OpenPOWER on IntegriCloud