document softraid and bioctl creation of softraid

ok marco@, help from jmc@

2 files changed, 93 insertions, 2 deletions

diff --git a/share/man/man4/Makefile b/share/man/man4/Makefile
index 559de66ccb5..b71e14b7aba 100644
--- a/share/man/man4/Makefile
+++ b/share/man/man4/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.409 2007/03/19 04:48:23 deraadt Exp $
+#	$OpenBSD: Makefile,v 1.410 2007/03/20 03:40:38 todd Exp $
 
 MAN=	aac.4 ac97.4 acphy.4 \
 	acpi.4 acpiac.4 acpibat.4 acpibtn.4 acpicpu.4 acpidock.4 \
@@ -39,7 +39,7 @@ MAN=	aac.4 ac97.4 acphy.4 \
 	rl.4 rln.4 rlphy.4 route.4 rt.4 rum.4 \
 	rtfps.4 rtii.4 rtw.4 safe.4 safte.4 san.4 sbus.4 scsi.4 sd.4 \
 	sdmmc.4 sdhc.4 ses.4 \
-	sequencer.4 sf.4 sf2r.4 sfr.4 siop.4 sis.4 sk.4 sl.4 sm.4 \
+	sequencer.4 sf.4 sf2r.4 sfr.4 siop.4 sis.4 sk.4 sl.4 sm.4 softraid.4 \
 	speaker.4 sppp.4 sqphy.4 ss.4 st.4 ste.4 stge.4 sti.4 stp.4 sv.4 \
 	systrace.4 tcic.4 tcp.4 termios.4 ti.4 tl.4 \
 	tlphy.4 tqphy.4 trm.4 trunk.4 tsl.4 tty.4 tun.4 twe.4 txp.4 \
diff --git a/share/man/man4/softraid.4 b/share/man/man4/softraid.4
new file mode 100644
index 00000000000..e2bf48f8337
--- /dev/null
+++ b/share/man/man4/softraid.4
@@ -0,0 +1,91 @@
+.\"	$OpenBSD: softraid.4,v 1.1 2007/03/20 03:40:38 todd Exp $
+.\"
+.\" Copyright (c) 2007 Todd T. Fries <todd@OpenBSD.org>
+.\"
+.\" Permission to use, copy, modify, and distribute this software for any
+.\" purpose with or without fee is hereby granted, provided that the above
+.\" copyright notice and this permission notice appear in all copies.
+.\"
+.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+.\"
+.Dd March 19, 2007
+.Dt SOFTRAID 4
+.Os
+.Sh NAME
+.Nm softraid
+.Nd Software RAID
+.Sh SYNOPSIS
+.Cd "softraid0 at root"
+.Cd "scsibus*  at softraid?"
+.Sh DESCRIPTION
+The
+.Nm
+driver provides RAID 1 capabilities to
+.Ox .
+.Pp
+It provides a single RAID level:
+.Bl -tag -width indent -offset indent
+.\" .It RAID 0
+.\" provides simple data striping across the components.
+.It RAID 1
+provides mirroring.
+.\" .It RAID 5
+.\" provides data striping across the components, with parity
+.\" distributed across all the components.
+.El
+.Pp
+See
+.Xr bioctl 8
+for more information on configuration of RAID sets.
+.Pp
+The first step to using the
+.Nm
+driver is to ensure that it is suitably configured in the kernel.
+This is done by adding the following lines
+to the kernel configuration file:
+.Bd -literal -offset indent
+softraid0       at root         # Software RAID
+scsibus*        at softraid?
+.Ed
+.Pp
+All component partitions must be of type
+.Dv RAID .
+Some platforms, such as SUN, are not capable of using the
+.Dv RAID
+partition type.  The
+.Dv 4.2BSD
+partition type should be used on such platforms.
+.Sh SEE ALSO
+.Xr sd 4 ,
+.Xr wd 4 ,
+.Xr bioctl 8 ,
+.Xr config 8 ,
+.Xr fsck 8 ,
+.Xr MAKEDEV 8 ,
+.Xr mount 8 ,
+.Xr newfs 8
+.Sh HISTORY
+The
+.Nm
+driver in
+.Ox
+is an original work by Marco Peereboom.
+It first appeared in
+.Ox 4.2 .
+.Sh CAVEATS
+RAID level 1 can protect against some
+data loss due to component failure.
+However the loss of all components of a RAID 0 system
+will result in the entire filesystems on that RAID device
+being lost.
+RAID is
+.Em not
+a substitute for good backup practices.
+.Sh BUGS
+The driver is currently unable to handle drive failures.