Is RAID 1 enough?

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Sternkreuzer

I am considering putting RAID 1 on the new machine I am building, with XP Pro.

Reading the documentation on the Intel motherboard it seems one needs to do
the <F6> tinkering with the BIOS at the very beginning of the installation of
XP Pro.

I like the RAID 1 concept, but what happens if the motherboard fails? Is
there a danger of losing all the data on the mirrored disks after replacing
the motherboard? It seems one would have to go through the <F6> procedure
again so the motherboard accepts a RAID configuration. Does that force a
Clean Install??
 
At face value, a backup hard drive that contains the contents of the boot
hard drive seems ideal. That's RAID 1.

However, most hard drives don't instantly fail. They show signs of
read/write problems intially. Some of these things are mirrored on the
backup hard drive automatically. The mirrored hard drive may or may not be
bootable on the same PC after such a scenario. All personal data may or may
not be available.
 
Sternkreuzer said:
I am considering putting RAID 1 on the new machine I am building,
with XP Pro.

Reading the documentation on the Intel motherboard it seems one
needs to do the <F6> tinkering with the BIOS at the very beginning
of the installation of XP Pro.

I like the RAID 1 concept, but what happens if the motherboard
fails? Is there a danger of losing all the data on the mirrored
disks after replacing the motherboard? It seems one would have to
go through the <F6> procedure again so the motherboard accepts a
RAID configuration. Does that force a Clean Install??
Click to expand...

A combination of any true raid (RAID0 is merely striping - JBOD) with
consistent scheduled external backups is the best assurance against data
loss and long rebuild times.

I don't like RAID1 because it only gives protection against catastrophic
*instant* failure of the first hard disk drive. If your computer gets
messed up in the way computers normally do (software/human intervention) -
that probably got replicated to the second drive and thus - you still lost
anything not backed up externally. ;-)
 
I am considering putting RAID 1 on the new machine I am building, with XP Pro.
Click to expand...


Why? Except for corporations, it's almost always a mistake.

Reading the documentation on the Intel motherboard it seems one needs to do
the <F6> tinkering with the BIOS at the very beginning of the installation of
XP Pro.

I like the RAID 1 concept,
Click to expand...


OK, but most people completely misunderstand what RAID 1 is all about.
RAID 1 (mirroring) is *not* a backup solution. RAID 1 uses two or more
drives, each a duplicate of the others, to provide redundancy, not
backup. It's used in situations (almost always within corporations,
not in homes) where any downtown can't be tolerated, because the way
it works is that if one drive fails the other takes over seamlessly.

Although some people thing of RAID 1 as a backup technique, that is
*not* what it is, since it's subject to simultaneous loss of the
original and the mirror to many of the most common dangers threatening
your data--severe power glitches, nearby lightning strikes, user
errors, virus attacks, theft of the computer, etc. Most companies that
use RAID 1 also have a strong external backup plan in place.

Read my thoughts on backup here:
http://www.computorcompanion.com/LPMArticle.asp?ID=314
 
Lil' Dave said:
At face value, a backup hard drive that contains the contents of the boot
hard drive seems ideal. That's RAID 1.

However, most hard drives don't instantly fail. They show signs of
read/write problems intially. Some of these things are mirrored on the
backup hard drive automatically. The mirrored hard drive may or may not be
bootable on the same PC after such a scenario. All personal data may or may
not be available.
Click to expand...

What do you think of Intel's "Matrix Storage" solution which I was reading
about recently at

http://www.intel.com/design/chipsets/matrixstorage_sb.htm

That seems to try to address the concerns you mentioned...
 
Shenan Stanley said:
A combination of any true raid (RAID0 is merely striping - JBOD) with
consistent scheduled external backups is the best assurance against data
loss and long rebuild times.

I don't like RAID1 because it only gives protection against catastrophic
*instant* failure of the first hard disk drive. If your computer gets
messed up in the way computers normally do (software/human intervention) -
that probably got replicated to the second drive and thus - you still lost
anything not backed up externally. ;-)
Click to expand...

What do you think of Intel's "Matrix Storage" solution which I was reading
about recently at

http://www.intel.com/design/chipsets/matrixstorage_sb.htm

That seems to try to address the concerns you mentioned...
 
Ken Blake said:
Why? Except for corporations, it's almost always a mistake.




OK, but most people completely misunderstand what RAID 1 is all about.
RAID 1 (mirroring) is *not* a backup solution. RAID 1 uses two or more
drives, each a duplicate of the others, to provide redundancy, not
backup. It's used in situations (almost always within corporations,
not in homes) where any downtown can't be tolerated, because the way
it works is that if one drive fails the other takes over seamlessly.

Although some people thing of RAID 1 as a backup technique, that is
*not* what it is, since it's subject to simultaneous loss of the
original and the mirror to many of the most common dangers threatening
your data--severe power glitches, nearby lightning strikes, user
errors, virus attacks, theft of the computer, etc. Most companies that
use RAID 1 also have a strong external backup plan in place.

Read my thoughts on backup here:
http://www.computorcompanion.com/LPMArticle.asp?ID=314
Click to expand...

I just finished reading your article and found it most informative. I would
like to pose the same question as to the previous replies:

What do you think of Intel's "Matrix Storage" solution which I was reading
about recently at

http://www.intel.com/design/chipsets/matrixstorage_sb.htm

They discuss using RAID 1, 5 or 10, presumably with internal Hard Drives,
and they also discuss making a Recovery Disk. However they do not seem to be
very clear about what the difference is between the two... They certainly
promote their methods as the ideal solution to solving the issues of keeping
the data of the home user safe.

Making an iso copy with Acronis True Image sounds like a great way to have a
recovery disk on hand. Is this product at the "user friendly" level? Also the
information about the danger that a full back-up poses when it overwrites the
old back-up is certainly an item to consider....
 
Sternkreuzer said:
I am considering putting RAID 1 on the new machine I am building,
with XP Pro.

Reading the documentation on the Intel motherboard it seems one
needs to do the <F6> tinkering with the BIOS at the very beginning
of the installation of XP Pro.

I like the RAID 1 concept, but what happens if the motherboard
fails? Is there a danger of losing all the data on the mirrored
disks after replacing the motherboard? It seems one would have to
go through the <F6> procedure again so the motherboard accepts a
RAID configuration. Does that force a Clean Install?
Click to expand...

Shenan said:
A combination of any true raid (RAID0 is merely striping - JBOD)
with consistent scheduled external backups is the best assurance
against data loss and long rebuild times.

I don't like RAID1 because it only gives protection against
catastrophic *instant* failure of the first hard disk drive. If
your computer gets messed up in the way computers normally do
(software/human intervention) - that probably got replicated to the
second drive and thus - you still lost anything not backed up
externally. ;-)
Click to expand...
What do you think of Intel's "Matrix Storage" solution which I was
reading about recently at

http://www.intel.com/design/chipsets/matrixstorage_sb.htm

That seems to try to address the concerns you mentioned...
Click to expand...

It does not address my concern(s) at all.

The "Matrix Storage Technology" is nothing new. 2004/2005ish?

In any case - RAID1 is still mirroring from one set of storage to another -
and in the case of hardware RAID1 (BTW - *I* would never recommend any
software RAID solution to anyone for any reason) it is usually instantaneous
mirroring.

If you have something mess up on the first storage device non-hardware
related (or even hardware where it scrambles a few files and is not
catastrophic and instant total failure) - it will replicate to the other
storage device and you have no good backups *if* that was your only solution
for such.

- Performance-wise - there is *no* benefit to RAID1 for the home consumer.
- Price-wise - you are losing money because you spent twice as much money on
something that gives you potentially nothing in return by itself.

Look into RAID5 further. Redundancy and continued functionality even during
a minor failure make it still the 'king' of RAID arrays for many people.
Yes - you cannot just have two disks - you have to have a minumum of three
and the hardware capable of doing a RAID5. However - with RAID5 - if you
lose any single disk - you continue to run and usually can *make* the time
available to you to replace the bad disk and continue working.

*However* - it has to be pointed out again - RAID is not a backup solution.
It is a redundancy (Redundant Array of Inexpensive Disks) solution - it
keeps you up and going for as much time as is feasibly possible - even
during single drive failures.

Consistent and scheduled backups to external media is still necessary if you
want a complete 'disaster recovery' type solution.

Performance-wise, there is a slight benefit to RAID0 (not true RAID in my
opinion) and RAID5, as you spread the load across more spindles. To be
quite honest though - most home users (even those hobbiest video editors,
music producers, etc) will never see the actual performance gain over just a
single large modern hard disk drive.

Some of the other (lesser known/lesser used) RAIDs have benefits and
disadvantages (as you would expect) - but none can I recommend as highly as
RAID5 for overall reliability and redundancy-type protection. (Although
someone doing serious video recording/video streaming might benefit from
RAID3...)
 
I just finished reading your article and found it most informative.
Click to expand...


Thank you. I'm glad to hear that.

I would
like to pose the same question as to the previous replies:

What do you think of Intel's "Matrix Storage" solution which I was reading
about recently at

http://www.intel.com/design/chipsets/matrixstorage_sb.htm
Click to expand...


I know nothing about it, but if it's RAID mirroring, I repeat that
it's a poor choice for home users.

They discuss using RAID 1, 5 or 10, presumably with internal Hard Drives,
Click to expand...


RAID is always with internal drives.

and they also discuss making a Recovery Disk. However they do not seem to be
very clear about what the difference is between the two... They certainly
promote their methods as the ideal solution to solving the issues of keeping
the data of the home user safe.
Click to expand...


I completely disagree. Again, don't mix up redundancy, which is what
RAID 1 provides, with backup.

The classic example of the need for redundancy is an airline
reservation system. If a drive is lost and the system has to go down
to restore a backup, *millions* of dollars in revenue can be lost
during the down time, because customers are fickle and will take their
business elsewhere while the system is down. Because that can't be
tolerated, redundancy is required, using RAID 1 (or some similar
mirroring system).

Home users very rarely have a need anything like that. If your system
is down for an hour or even a few, while you restore from a backup, it
may be a minor nuisance, but that's all. The home user needs, most of
all, to be sure that the backup always exists. That's why it's
critical that backup be on external media, not stored within the
computer.


Making an iso copy with Acronis True Image sounds like a great way to have a
recovery disk on hand. Is this product at the "user friendly" level?
Click to expand...


Yes, I think it's very easy to use.

Also the
information about the danger that a full back-up poses when it overwrites the
old back-up is certainly an item to consider....
Click to expand...


That's why the best choice is to use two (or more) external drives,
and alternate between them. That way the act of creating a backup is
never also the act of destroying your only backup.

Especially in these days of very inexpensive hard drives, that latter
alternative is what I recommend.
 
Many Thanks for the help on this topic. This has given me a fresh and much
broader picture of what is going on with system recovery and backup. I had
not run across the clear distinction between redundancy and backup that has
been presented here.
 
Many Thanks for the help on this topic. This has given me a fresh and much
broader picture of what is going on with system recovery and backup. I had
not run across the clear distinction between redundancy and backup that has
been presented here.
Click to expand...


You're welcome. Glad to help.
 
Depends on the actual RAID controller. Usually, RAID 1 pairs can be split and
will work as standard disks without any changes being needed other than
perhaps the partition-type byte. Not so other RAID types. A key concern with
RAID 5/10 is failure of the controller itself, which may leave the data
inaccessible.

I've had the situation where a bad disk took-out the data on its partner as
well as its own. In this case mirroring INCREASED the chance of disk-failure
from 50%, (depending which of the two disks I'd chosen as a standalone) to
100% if both were in use as a mirror pair. Not good! The chances of this
happening are less with separate disk-controllers, greater if both disks are
 
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