[PLUG] organizing files on software Raid (SCSI)

[Wayne Dawson <jongalt@pinn.net>]

Hello, I am trying to set up a computer to use software RAID, and put as 
much as I can on the RAID.  I have seen some indications that I can't boot 
from a software RAID (although other places I have seen contrary information).

Here's the result of df:
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/hda5               505605    179305    300196  38% /
/dev/hda1               101089     17580     78290  19% /boot
/dev/hda3              7337124     32876   6931540   1% /home
none                    127176         0    127176   0% /dev/shm
/dev/hda2             20050176   3972764  15058892  21% /usr
/dev/hda6              1027768    168644    806916  18% /var
/dev/md0              17639128     32836  16710276   1% /mnt/softraid

(By the way, I haven't figured out how to put the RAID into /etc/fstab, but 
I suspect it won't normally be mounted as /mnt/softraid anyway.)

I don't know what /dev/shm is (is it related to this?), but I created 
/dev/md0 from /dev/sda1 and /dev/sdb1, using mdadm -C.  The SCSI hard disks 
are in a cabinet separate from the computer, but /dev/hda is a plain old 
IDE drive in the computer.

I'm using Red Hat 8.

Here's the result of lsmod (apparently whether SCSI and/or RAID software is 
compiled into the kernel is relevant to booting from a SCSI RAID):
Module                  Size  Used by    Not tainted
vfat                   13084   0  (autoclean)
fat                    38712   0  (autoclean) [vfat]
raid1                  15276   1  (autoclean)
ide-cd                 33608   0  (autoclean)
cdrom                  33696   0  (autoclean) [ide-cd]
emu10k1                68744   0  (autoclean)
ac97_codec             13384   0  (autoclean) [emu10k1]
sound                  74388   0  (autoclean) [emu10k1]
soundcore               6532   7  (autoclean) [emu10k1 sound]
i810                   72736   1
agpgart                43072   7  (autoclean)
binfmt_misc             7524   1
autofs                 13348   0  (autoclean) (unused)
3c59x                  30640   1
iptable_filter          2412   0  (autoclean) (unused)
ip_tables              14936   1  [iptable_filter]
microcode               4668   0  (autoclean)
mousedev                5524   1
keybdev                 2976   0  (unused)
hid                    22244   0  (unused)
input                   5888   0  [mousedev keybdev hid]
usb-uhci               26188   0  (unused)
usbcore                77024   1  [hid usb-uhci]
ext3                   70368   6
jbd                    52212   6  [ext3]
aic79xx               212516   2
sd_mod                 13552   4
scsi_mod              107144   2  [aic79xx sd_mod]

So here's my question:  what's the best way to *expediently* maximize how 
much of my data can be stored on the RAID?  (ie. How should I organize 
everything?  Can I arrange to boot from RAID with, for example, nothing but 
GRUB on the IDE drive?  Or even without anything on the IDE drive?  I guess 
that would involve recompiling the kernel.)

Anyway, thanks for any assistance,
Wayne

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