RAID question (A8V Deluxe)

[Hackworth]

I want to set up a RAID 1 array to add a little extra data security. I've
already purchased another hard disk that's the exact make/model of the one
already in my system (a 160-GB Western Digital WD1600JD).

My motherboard (an A8V Deluxe) has both the VIA K8T800Pro chipset supporting
two Serial ATA connectors with RAID 0, RAID 1, and JBOD functions, *and* a
Promise FastTrack 20378 controller providing another two Serial ATA
connectors for RAID 0, RAID 1, RAID 0+1, and multiple RAID functions.

Which one should I use? Are they both considered "hardware RAID" solutions
and, if so, is there much of a performance difference between the two?
Obviously, I'm not a RAID expert, and this is my first foray into the world
of RAID, so I'd appreciate any helpful advice from the more experience
RAIDers in this group.

 

[Leythos]

I want to set up a RAID 1 array to add a little extra data security. I've
already purchased another hard disk that's the exact make/model of the one
already in my system (a 160-GB Western Digital WD1600JD).

My motherboard (an A8V Deluxe) has both the VIA K8T800Pro chipset supporting
two Serial ATA connectors with RAID 0, RAID 1, and JBOD functions, *and* a
Promise FastTrack 20378 controller providing another two Serial ATA
connectors for RAID 0, RAID 1, RAID 0+1, and multiple RAID functions.

Which one should I use? Are they both considered "hardware RAID" solutions
and, if so, is there much of a performance difference between the two?
Obviously, I'm not a RAID expert, and this is my first foray into the world
of RAID, so I'd appreciate any helpful advice from the more experience
RAIDers in this group.

RAID 1+0 provides speed and redundancy.

RAID 1 provides redundancy with read performance

RAID 0 Provides read/write performance and higher risk of loss

 

[Hackworth]

RAID 1+0 provides speed and redundancy.

RAID 1 provides redundancy with read performance

RAID 0 Provides read/write performance and higher risk of loss

I know that. I see now that I worded my question stupidly. I meant which
onboard RAID *controller* should I use, the chipset-provided RAID or the
Promise RAID?

 

[Leythos]

I know that. I see now that I worded my question stupidly. I meant which
onboard RAID *controller* should I use, the chipset-provided RAID or the
Promise RAID?

I've been using BOTH at time, although not with that board, but I start
with the Promise and then use the Intel if needed.

 

[Paul]

I know that. I see now that I worded my question stupidly. I meant which
onboard RAID *controller* should I use, the chipset-provided RAID or the
Promise RAID?

Also, if you set up a RAID 1 array, you should go through the exercise
of what to do when the RAID BIOS indicates a problem. For example,
create the mirror, format and partition in Windows, place say one
test file on it. Now, shut down and remove one disk drive of the
pair in the RAID array. What does the BIOS do ?

Now, remove the first drive (the one that was present when the problem
was recognized). Take the second drive and zero it, if you can find
a utility that can zap the whole drive. Or use the RAID BIOS to
delete the array information on that drive. This will be your virgin
"replacement disk", to simulate doing a replacement. Install
both disks (the one with the data, the virgin replacement), and
go through the exercise of rebuilding the array.

You can also simulate a case where the second drive is not damaged.
Start the system with only one member of the array present. Boot
up and shut down. Now, install the second drive again. What question
does the BIOS ask you ? Do you have to "Delete" then "Create" the
array again ? Since this test case arises more frequently, you
are more likely to see it. Maybe once every couple of months,
one of the drives will be a little slow at power up, and that
is enough to "break" the array.

Always work through the scenarios for the array, so you'll know
what to do when real valuable data is on it. People really
get uptight, when the disk is full of data, there are no backups,
and the RAID BIOS has bad news for them. And the people in this
newsgroup will not know every nuance of every RAID BIOS out
there.

You'll get an especially good workout with RAID 0+1. In that
case, some RAID BIOS are better designed than others, at
identifying what drive to replace or how to do a rebuild.

And you still need to do backups...

Paul

 

[Leythos]

Always work through the scenarios for the array, so you'll know
what to do when real valuable data is on it. People really
get uptight, when the disk is full of data, there are no backups,
and the RAID BIOS has bad news for them. And the people in this
newsgroup will not know every nuance of every RAID BIOS out
there.

You'll get an especially good workout with RAID 0+1. In that
case, some RAID BIOS are better designed than others, at
identifying what drive to replace or how to do a rebuild.

I never thought to mention that to people - but it's the first thing
that most people get wrong when their array goes t-up.

And you still need to do backups...

That is the most important part of this entire thread

 

[Hackworth]

Also, if you set up a RAID 1 array, you should go through the exercise
of what to do when the RAID BIOS indicates a problem. For example,
create the mirror, format and partition in Windows, place say one
test file on it. Now, shut down and remove one disk drive of the
pair in the RAID array. What does the BIOS do ?

Now, remove the first drive (the one that was present when the problem
was recognized). Take the second drive and zero it, if you can find
a utility that can zap the whole drive. Or use the RAID BIOS to
delete the array information on that drive. This will be your virgin
"replacement disk", to simulate doing a replacement. Install
both disks (the one with the data, the virgin replacement), and
go through the exercise of rebuilding the array.

You can also simulate a case where the second drive is not damaged.
Start the system with only one member of the array present. Boot
up and shut down. Now, install the second drive again. What question
does the BIOS ask you ? Do you have to "Delete" then "Create" the
array again ? Since this test case arises more frequently, you
are more likely to see it. Maybe once every couple of months,
one of the drives will be a little slow at power up, and that
is enough to "break" the array.

Always work through the scenarios for the array, so you'll know
what to do when real valuable data is on it. People really
get uptight, when the disk is full of data, there are no backups,
and the RAID BIOS has bad news for them. And the people in this
newsgroup will not know every nuance of every RAID BIOS out
there.

You'll get an especially good workout with RAID 0+1. In that
case, some RAID BIOS are better designed than others, at
identifying what drive to replace or how to do a rebuild.

And you still need to do backups...

Excellent information for a RAID n00b like me, Paul. Many thanks for your
time. I'm going to archive this reply.

And I agree about the backups wholeheartedly and will continue to do them.
You're preaching to the choir in this case. ;-)

 

[Wayne]

I know that. I see now that I worded my question stupidly. I meant which
onboard RAID *controller* should I use, the chipset-provided RAID or the
Promise RAID?

On my A8V Deluxe, the VIA Raid controller is a little faster than the Promise
(VIA works direct from chipset, Promise is on the PCI buss).

For example, I use two WD 80GB drives in RAID 0. On the Promise, HDTach
reports 65MB/second average over the full disk (rim to spindle). On the VIA,
the same drives report 76MB/second. In comparison, a singe WD 160 drive shows
53MB/second, and a single WD 320 shows 57MB/second.

So I like RAID 0 for the higher performance. My thinking is that since I do
regular full Ghost backups every week anyway, then the theoretical higher
failure rate potentional is not important to me - I can simply restore the
Ghost backup. I also backup my few important data folders every day.

 

[Hackworth]

On my A8V Deluxe, the VIA Raid controller is a little faster than the
Promise
(VIA works direct from chipset, Promise is on the PCI buss).

Precisely the information I was seeking, Wayne. Thanks. I just wanted to
save a little time by seeing if anyone else in this group could speak from
personal experience. This afternon, I went ahead and set up my RAID1 array
on the Via 8237 chipset-controlled SATA connectors, and everything went off
without a hitch. I'll save the two Promise SATA connectors in case I ever
want to add another hard disk in the future... which I seriously doubt will
happen anyway. If I have lots of free money someday (ha ha), I'll get two WD
Raptors and set them up in RAID0 on the Via controller, with big fat storage
drives in RAID1 on the Promise controller.

For example, I use two WD 80GB drives in RAID 0. On the Promise, HDTach
reports 65MB/second average over the full disk (rim to spindle). On the
VIA,
the same drives report 76MB/second. In comparison, a singe WD 160 drive
shows
53MB/second, and a single WD 320 shows 57MB/second.

So I like RAID 0 for the higher performance. My thinking is that since I
do
regular full Ghost backups every week anyway, then the theoretical higher
failure rate potentional is not important to me - I can simply restore the
Ghost backup. I also backup my few important data folders every day.

Very good. You should be in great shape then. I back up all of my personal
files about once a week onto DVD and that works for me. I've been looking
into getting a NAS to connect to the network for an added bit of redundancy,
and so that everyone else in the house has an extra place to back up stuff
from their computers. We'll see.