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diff --git a/static/netbsd/man4/ccd.4 b/static/netbsd/man4/ccd.4 new file mode 100644 index 00000000..89292b2c --- /dev/null +++ b/static/netbsd/man4/ccd.4 @@ -0,0 +1,161 @@ +.\" $NetBSD: ccd.4,v 1.32 2014/10/27 16:20:48 wiz Exp $ +.\" +.\" Copyright (c) 1996, 1997 The NetBSD Foundation, Inc. +.\" All rights reserved. +.\" +.\" This code is derived from software contributed to The NetBSD Foundation +.\" by Jason R. Thorpe. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS +.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS +.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +.\" POSSIBILITY OF SUCH DAMAGE. +.\" +.\" Copyright (c) 1994 Jason Downs. +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS +.\" OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +.\" DISCLAIMED. IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, +.\" INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.Dd November 30, 2013 +.Dt CCD 4 +.Os +.Sh NAME +.Nm ccd +.Nd Concatenated disk driver +.Sh SYNOPSIS +.Cd pseudo-device ccd +.Sh DESCRIPTION +The +.Nm +driver provides the capability of combining one or more disks/partitions +into one virtual disk. +.Pp +This document assumes that you're familiar with how to generate kernels, +how to properly configure disks and pseudo-devices in a kernel +configuration file, and how to partition disks. +.Pp +Note that the +.Sq raw +partitions of the disks +.Pa must not +be combined. +Each component partition should be offset at least one cylinder +from the beginning of the component disk. +This avoids potential conflicts between the component disk's +disklabel and the +.Nm Ns 's +disklabel. +The kernel will only allow component partitions of type +.Dv FS_CCD . +But for now, it allows partition of all types since some port +lacks support of an on-disk BSD disklabel. +The partition of +.Dv FS_UNUSED +may be rejected because device driver of component disk will refuse it. +.Pp +In order to compile in support for the +.Nm , +you must add a line similar +to the following to your kernel configuration file: +.Bd -unfilled -offset indent +pseudo-device ccd # concatenated disk devices +.Ed +.Pp +The +.Nm Ns s +are allocated dynamically as needed. +.Pp +A +.Nm +may be either serially concatenated or interleaved. +To serially concatenate the partitions, specify the interleave factor of 0. +.Pp +If a +.Nm +is interleaved correctly, a +.Dq striping +effect is achieved, which can increase performance. +.\" The optimum interleave factor is typically the size of a track, +.\" see +.\" .Dq sectors/track +.\" value in +.\" .Xr disklabel 8 +.\" output. +Since the interleave factor is expressed in units of +.Dv DEV_BSIZE , +one must account for sector sizes other than +.Dv DEV_BSIZE +in order to calculate the correct interleave. +The kernel will not allow an interleave factor less than the size +of the largest component sector divided by +.Dv DEV_BSIZE . +.Pp +Note that best performance is achieved if all component disks have the same +geometry and size. +Optimum striping cannot occur with different disk types. +.Pp +Also note that the total size of concatenated disk may vary depending on +the interleave factor even if the exact same components are concatenated. +And an old on-disk disklabel may be read after interleave factor change. +As a result, the disklabel may contain wrong partition geometry and +will cause an error when doing I/O near the end of concatenated disk. +.Pp +There is a run-time utility that is used for configuring +.Nm Ns s . +See +.Xr ccdconfig 8 +for more information. +.Sh WARNINGS +If just one (or more) of the disks in a non-mirrored +.Nm +fails, the entire file system will be lost. +.Sh FILES +.Bl -tag -width /dev/XXrXccdX -compact +.It Pa /dev/{,r}ccd* +.Nm +device special files. +.El +.Sh SEE ALSO +.Xr config 1 , +.Xr ccdconfig 8 , +.Xr fsck 8 , +.Xr MAKEDEV 8 , +.Xr mount 8 , +.Xr newfs 8 +.Sh HISTORY +The concatenated disk driver was originally written at the University of Utah. |