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- '\" Copyright 1990 Regents of the University of California
- '\" Permission to use, copy, modify, and distribute this
- '\" documentation for any purpose and without fee is hereby
- '\" granted, provided that this notice appears in all copies.
- '\" The University of California makes no representations about
- '\" the suitability of this material for any purpose. It is
- '\" provided "as is" without express or implied warranty.
- '\"
- '\" $Header: /sprite/src/man/dev/RCS/raid.man,v 1.2 92/09/04 16:19:44 eklee Exp Locker: eklee $ SPRITE (Berkeley)
- '/"
- .so \*(]ltmac.sprite
- .HS RAID dev
- .BS
- '\" Note: do not modify the .SH NAME line immediately below!
- .SH NAME
- raid \- Devices used to send ioctl's to RAID devices.
- .SH SYNOPSIS
- \fB#include <dev/raid.h>\fR
- .BE
-
- .SH OVERVIEW
- .PP
- This document describes the configuration and management of raid devices.
-
- .SH THE RAID CONFIGURATION FILE
- .PP
- An example RAID configuration file is as follows:
- .DS
- .in -12
- # R L S N
- # 512B 32KB 323MB
- #numRow numCol logSectSize sectPerSU SUPerDisk parityConfig logDev(d,u,offset)
- 1 4 9 64 9859 L 516 5128 0
- 516 7176
- 516 7192
- 516 7208
- 516 7224
- .DE
-
- Lines starting with '#' are considereded comments. Comments can only occure
- at the BEGINNING of the configuration file.
- .IP numRow, numCol
- The number of rows and columns of disks in the disk array. Parity is computed
- accross the disks in each row.
- .IP logSectSize
- The log base 2 of the sector size. A 9 => 2^9 = 512 byte sectors.
- .IP sectPerSU
- The number of sectors per stripe unit. The stripe unit is the amount of data
- placed on a given disk before data is placed on the next disk.
- .IP SUPerDisk
- The number of stripe units per disk.
- .IP parityConfig
- The parity configuration to use. L => left-symmetric (the best all-around
- choice), R => right-symmetric, N => RAID level 4 placement and S => do not
- compute parity; i.e., only data striping.
- .IP logDev
- The type, unit and device offset for the log disk. By specifying different
- offsets, the same disk can be used as the log for several disk arrays.
- If the parity configuration is S, logging is not neccessary and this field
- should be set to -1 -1 -1 instead of 516 5128 0 in the above example.
- .LP
- The rest of the file contains a list of the type and unit number of each disk
- in the disk array.
-
- .SH ADDING A NEW RAID DEVICE
-
- .DS
- .in -12
- Create a new raid device ($x = new raid device number):
- -- If necessary, create:
- fsmakedev -d 10 -u $x /dev/raid$x
- fsmakedev -d 10 -u $x /dev/raid${x}a
- -- Create raid configuration file /boot/cmds/RAID$x.config.
- -- Issue IOC's to configure new device:
- If parityConfig == 'S' (i.e. no parity, only data striping)
- /boot/cmds/raidioc /dev/raid$x reconfig /boot/cmds/RAID$x.config
- else
- /boot/cmds/raidioc /dev/raid$x reconfig /boot/cmds/RAID$x.config
- /boot/cmds/raidioc /dev/raid$x savestate
- /boot/cmds/raidioc /dev/raid$x hardinit 0 -1
- /boot/cmds/raidioc /dev/raid$x enablelog
- /boot/cmds/raidioc /dev/raid$x unlock
- endif
- -- Add commands to /hosts/<machine name>/bootcmds to restore existing
- raid device on system boots.
- If parityConfig == 'S' (i.e. no parity, only data striping)
- /boot/cmds/raidioc /dev/raid$x reconfig /boot/cmds/RAID$x.config
- else
- /boot/cmds/raidioc /dev/raid$x restorestate <logDev(d,u,offset)> && \
- /boot/cmds/raidioc /dev/raid$x enablelog && \
- /boot/cmds/raidioc /dev/raid$x unlock
- endif
- -- Add new device to ~eklee/bin/paritycheckraid if automatic periodic
- parity checks are desired.
- .DE
-
- .SH ADDING A NEW RAID LFS FILE SYSTEM
-
- .DS
- .in -12
- -- Find out numSector and dataBytesPerStripe (printed to /dev/syslog).
- /boot/cmds/raidioc /dev/raid$x print
- -- labeldisk -w /dev/raid$x # use numSector info here
- -- mklfs -segAlignment <dataBytesPerStripe> /dev/raid0
- -- If necessary create:
- cd /
- ln -r /r$x
- -- Mount file system:
- prefix -M /dev/raid$x -l /r$x
- -- Add commands to /hosts/<machine name>/bootcmds to automatically
- export file system.
- prefix -M /dev/raid$x -l /r$x
- .DE
-
- .SH SEE ALSO
-
- .SH KEYWORDS
- raid command, raid device
-