P4C800E del. RAID0+1

[Rob Hemmings]

Is there a definitive guide/site to setting up RAID0+1 on a P4C800E
deluxe that anyone knows about? I'm sure I saw something on this
ng ages ago, but can't seem to find it in the archives. The manual is
a little confusing/sparse. So far, for 250GB of RAID0+1, I think I
need 2x250GB SATAs on the Promise controller for the RAID0
striped array and 1x250GB PATA on the ICH5R controller to mirror
this using RAID1, or have I got that wrong?
Also, is it possible to have the system boot from a 4th HD which
just contains the OS (XP pro) with the RAID0+1 array used only
to store data (fyi, it's for a video editing suite.)
Ta,

 

[Paul]

Is there a definitive guide/site to setting up RAID0+1 on a P4C800E
deluxe that anyone knows about? I'm sure I saw something on this
ng ages ago, but can't seem to find it in the archives. The manual is
a little confusing/sparse. So far, for 250GB of RAID0+1, I think I
need 2x250GB SATAs on the Promise controller for the RAID0
striped array and 1x250GB PATA on the ICH5R controller to mirror
this using RAID1, or have I got that wrong?
Also, is it possible to have the system boot from a 4th HD which
just contains the OS (XP pro) with the RAID0+1 array used only
to store data (fyi, it's for a video editing suite.)
Ta,

They tend not to name the Southbridge associated with the
feature set, so I presume the first one is for ICH5R.

ftp://download.intel.com/support/chipsets/iaa/manual2.pdf

This one mentions Matrix RAID and ICH6R (i.e. after P4C800-E)

ftp://download.intel.com/support/chipsets/imst/sb/manual3oem.pdf

This could be a slightly later release of Matrix RAID manual.
It has a troubleshooting section in the back.

ftp://download.intel.com/support/chipsets/imst/sb/manual45_oem.pdf

I have yet to see any RAID features cross between hardware devices.
The RAID on the Southbridge is independent of the RAID on the
Promise 20378 controller. Unless you are using some kind of
software RAID, such as the RAID5 hack on tomshardware.com, then
generally full support for RAID in the BIOS, and by the drivers,
is per-chip only.

Perhaps a third party product, could do mirroring between two
arrays you defined at the hardware level ?

The Promise 20378 has two SATA and room for two IDE on one
cable. You can do 0+1 on the Promise, which would take four
drives. It would take two SATA and two PATA drives. In terms
of performance, I don't know if it would be better to stripe
a SATA+PATA, and then mirror against the other SATA+PATA, or
to build SATA+SATA and mirror against PATA+PATA. (You may not
even get to choose which config.) As one poster recently noted,
two drives on the same IDE cable, costs maybe 25% in terms of
STR, and the two PATA drives might conflict no matter how you
did the 0+1 for the four drives.

It looks like the section in the Asus P4C800-E manual,
concerning the Promise RAID, is actually better than
the Promise document included in the motherboard CD "manual"
folder. (While you could look for a manual on the Promise
site, for one of their RAID cards, the capabilities in the
BIOS screens are bound to be a bit different.)

I think for your usage, the ICH5R is not going to help. It
supports RAID 0 or RAID 1 on the two SATA ports off the
Southbridge.

Wish I could help with software solutions, but I've never seen
a posting from someone using a separate after-market software
RAID package. The Tomshardware hack for RAID5 is here, and
should be able to work on any hardware interface that does
a vanilla disk interface (meaning you could do a software
RAID5 using interfaces on both the Southbridge and the
Promise chip).

http://www.tomshardware.com/storage/20041119/index.html

Once you've set up the four drives on the Promise chip, do
some failure scenarios on the array. At least one poster
has been confused about what to do, when a stripe loses a
drive - whether the mirror has to be broken and remade or
whatever.

Paul

 

[Rob Hemmings]

They tend not to name the Southbridge associated with the
feature set, so I presume the first one is for ICH5R.

ftp://download.intel.com/support/chipsets/iaa/manual2.pdf

This one mentions Matrix RAID and ICH6R (i.e. after P4C800-E)

ftp://download.intel.com/support/chipsets/imst/sb/manual3oem.pdf

This could be a slightly later release of Matrix RAID manual.
It has a troubleshooting section in the back.

ftp://download.intel.com/support/chipsets/imst/sb/manual45_oem.pdf

I have yet to see any RAID features cross between hardware devices.
The RAID on the Southbridge is independent of the RAID on the
Promise 20378 controller. Unless you are using some kind of
software RAID, such as the RAID5 hack on tomshardware.com, then
generally full support for RAID in the BIOS, and by the drivers,
is per-chip only.

Perhaps a third party product, could do mirroring between two
arrays you defined at the hardware level ?

The Promise 20378 has two SATA and room for two IDE on one
cable. You can do 0+1 on the Promise, which would take four
drives. It would take two SATA and two PATA drives. In terms
of performance, I don't know if it would be better to stripe
a SATA+PATA, and then mirror against the other SATA+PATA, or
to build SATA+SATA and mirror against PATA+PATA. (You may not
even get to choose which config.) As one poster recently noted,
two drives on the same IDE cable, costs maybe 25% in terms of
STR, and the two PATA drives might conflict no matter how you
did the 0+1 for the four drives.

It looks like the section in the Asus P4C800-E manual,
concerning the Promise RAID, is actually better than
the Promise document included in the motherboard CD "manual"
folder. (While you could look for a manual on the Promise
site, for one of their RAID cards, the capabilities in the
BIOS screens are bound to be a bit different.)

I think for your usage, the ICH5R is not going to help. It
supports RAID 0 or RAID 1 on the two SATA ports off the
Southbridge.

Wish I could help with software solutions, but I've never seen
a posting from someone using a separate after-market software
RAID package. The Tomshardware hack for RAID5 is here, and
should be able to work on any hardware interface that does
a vanilla disk interface (meaning you could do a software
RAID5 using interfaces on both the Southbridge and the
Promise chip).

http://www.tomshardware.com/storage/20041119/index.html

Once you've set up the four drives on the Promise chip, do
some failure scenarios on the array. At least one poster
has been confused about what to do, when a stripe loses a
drive - whether the mirror has to be broken and remade or
whatever.

Many, many thanks, Paul. Things are somewhat clearer in my
mind now - especially the need to use only the Promise with 4
HDs for a 0+1 array, which seems to be where I lost the plot.
I'll have a good read through all of those docs before I begin.

The tomshardware RAID 5 s/w hack does look interesting.
I used to run a Novell server with RAID5, but that was SCSI
throughout and (seemed) simpler to setup, but I expect that
was because using RAID5 was fairly normal for this use, was
supported in hardware and, consequently, there was a fair
amount of doc. about for it, especially as it used 'ubiquitous'
Adaptec SCSI controllers.

I'll certainly be simulating failure scenarios with the 0+1
array before I commit any data to it - something that all
server admins know/learn; A disaster recovery procedure
that hasn't been properly tested, isn't!

Thanks once again & regards,

 

[Mercury]

Rob,

most people that use raid 0 for video editing indicate that they use the
raid only for the work files so are prepared for disc failures and total
data loss. They don't tend to mention wanting to mirror or otherwise add
data resilience...

RAID 0 on the ICH5R would give best performance (due to it not being limited
by the PCI Bus) if you concluded the same as above... this would mean moving
'system' and you could always mirror that on the promise using 2 x SATA...

HTH

 

[Rob Hemmings]

Mercury,
Thanks for that. Unfortunately it won't be used only for NLE but
will also hold a large database which is the reason for the mirror.
Useful and food for thought, anyway - there are several possible
scenarios and I need to pore over them and their possible
consequences.
Regards,
--
Rob

Rob,

most people that use raid 0 for video editing indicate that they use the
raid only for the work files so are prepared for disc failures and total
data loss. They don't tend to mention wanting to mirror or otherwise add
data resilience...

RAID 0 on the ICH5R would give best performance (due to it not being limited
by the PCI Bus) if you concluded the same as above... this would mean moving
'system' and you could always mirror that on the promise using 2 x SATA...

HTH