diff options
author | ru <ru@FreeBSD.org> | 2004-07-02 21:45:06 +0000 |
---|---|---|
committer | ru <ru@FreeBSD.org> | 2004-07-02 21:45:06 +0000 |
commit | 46fddaa54b09baa407fa66a14d46c0cc3a906e60 (patch) | |
tree | 602e903272257a1c5b455a48800dcaa680741026 /sbin/ccdconfig | |
parent | 20fbd172b22ab587e9d796f4cb8664a235cebe78 (diff) | |
download | FreeBSD-src-46fddaa54b09baa407fa66a14d46c0cc3a906e60.zip FreeBSD-src-46fddaa54b09baa407fa66a14d46c0cc3a906e60.tar.gz |
Mechanically kill hard sentence breaks.
Diffstat (limited to 'sbin/ccdconfig')
-rw-r--r-- | sbin/ccdconfig/ccdconfig.8 | 60 |
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 |