Document softraid boot process for i386/amd64.

Requested by Adam Thompson.
suggestions and ok deraadt, earlier version ok jmc

1 files changed, 32 insertions, 6 deletions

diff --git a/share/man/man4/softraid.4 b/share/man/man4/softraid.4
index 1b7b4244404..174a444f5ea 100644
--- a/share/man/man4/softraid.4
+++ b/share/man/man4/softraid.4
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: softraid.4,v 1.31 2013/03/12 14:00:57 jmc Exp $
+.\"	$OpenBSD: softraid.4,v 1.32 2013/10/28 15:15:08 stsp Exp $
 .\"
 .\" Copyright (c) 2007 Todd T. Fries   <todd@OpenBSD.org>
 .\" Copyright (c) 2007 Marco Peereboom <marco@OpenBSD.org>
@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: March 12 2013 $
+.Dd $Mdocdate: October 28 2013 $
 .Dt SOFTRAID 4
 .Os
 .Sh NAME
@@ -107,6 +107,21 @@ discipline.
 It writes data to each chunk in sequence to provide increased capacity.
 CONCAT does not provide redundancy.
 .El
+.Pp
+.Xr installboot 8
+may be used to install
+.Xr boot 8
+in
+.Nm
+volume meta data to allow booting from the volume.
+Boot support is currently limited to the CRYPTO and RAID 1 disciplines
+on amd64 and i386 platforms.
+At the
+.Xr boot 8
+prompt, softraid volumes have names beginning with
+.Sq sr
+and can be booted from like a normal disk device.
+CRYPTO volumes will require a decryption passphrase or keydisk at boot time.
 .Sh EXAMPLES
 An example to create a 3 chunk RAID 1 from scratch is as follows:
 .Pp
@@ -153,11 +168,26 @@ The RAID volume is now ready to be used as a normal disk device.
 See
 .Xr bioctl 8
 for more information on configuration of RAID sets.
+.Pp
+Install
+.Xr boot 8
+on the RAID volume:
+.Bd -literal -offset indent
+# /usr/mdec/installboot /boot /usr/mdec/biosboot sd0
+.Ed
+.Pp
+At the
+.Xr boot 8
+prompt, load the /bsd kernel from the RAID volume:
+.Bd -literal -offset indent
+boot> boot sr0a:/bsd
+.Ed
 .Sh SEE ALSO
 .Xr bio 4 ,
 .Xr bioctl 8 ,
 .Xr disklabel 8 ,
 .Xr fdisk 8 ,
+.Xr installboot 8 ,
 .Xr newfs 8
 .Sh HISTORY
 The
@@ -178,10 +208,6 @@ This is due to the scrub functionality not being currently implemented.
 .Pp
 Currently there is no automated mechanism to recover from failed disks.
 .Pp
-.Nm
-has boot support only for the CRYPTO and RAID 1 disciplines,
-and only on amd64 and i386 platforms.
-.Pp
 Sparc hardware needs to use fstype
 .Dq 4.2BSD
 instead of