to RAID or not to RAID?

[quanttrade99z]

Hello All

I need some advice on RAID.

I'm putting together a system for running stock trading. For me, this system is mission critical. (I know, I know, you guys don't believe me...)

Anyway, I am trying to figure out if I should configure it with RAID. I suppose it would be RAID 1 for safety.

I hestitate to do this because I have never used RAID before and worry it will cause me lots of headaches in the future, I won't know what to do it if crashes, it might limit me, etc etc.

What do you all think?

The original system will have 2 hard drives, maybe configured as RAID 1.

Specific questions:
Is Raid 1 easy to use?
Does it slow down the computer? (with all that extra writing?)
Can I then add a 3rd harddrive to use for other purposes which is not part of the RAID 1?
Are there any good anandtech postings on RAID (i looked but couldn't find any).

Thank you all!

 

[mooseracing]

Originally posted by: quanttrade99z
The original system will have 2 hard drives, maybe configured as RAID 1.

Specific questions:
Is Raid 1 easy to use?

All RAID is to me. It is setup that can be a pain. But a simple setup like RAID 0,1,5 are easy to do.

Does it slow down the computer? (with all that extra writing?)

Yes there will be slower data writing but reads will be good. It is nothing you will notice that much unless you are doing alot of data writes.

Can I then add a 3rd harddrive to use for other purposes which is not part of the RAID 1?

Yes, don't add it to the array.

Are there any good anandtech postings on RAID (i looked but couldn't find any).

Google is your friend. There are way too many sites out there on RAID setup an dinformation about all the different kinds.

 

[ochadd]

RAID 1 setup on XP is pretty easy but you do need a floppy drive. The RAID drivers are installed prior to installing windows.

It will not slow your computer. Not anything a human can detect anyway. Sometimes after a crash or hard memory failure it may run a check which will slow things down temporarily but that's a very rare occurance.

Yes you can add a 3rd drive to your system as a stand alone unit with no issues. Some controllers will actually allow you to use it as a hot spare if you want to be extra cautious.

Your search is as good as mine but I know I've read a few in the past.

RAID 1 is great and I've ran that in every business desktop for many years. If a drive crashes your computer will boot as normal and depending on the controller monitoring software, Intel, Nvidia, etc. you will get an error telling you the RAID array has been damaged, deteriorated, diminished capacity, etc. You could then rebuild the array with another drive of the same capacity, speed, and preferably the exact same model.

 

[Rike]

For data safety, you do not want to use RAID 0. With RAID 1 you take a hit on write performance, but I doubt you'll notice unless you are writing large chunks of data frequently. You also might consider RAID 5 (3 drives min), a good combo of redundancy and capacity.

Regardless of which RAID you go with, don't forget daily on-site and off-site backups if you really need your data, because RAID only protects you from HD failure, not system failure.

 

[cuti7399]

i vote for raid10 because of redundancy and capacity, require 4 drives but rebuild time is 90% faster then raid5.
Still recommend backup though!

 

[supremelaw]

Yes: RAID 10, or RAID 6 if you can afford the extra expense
of controllers that support RAID 6 and the extra number of HDDs
that are required.

"Mission critical" to me means that, even in the event of a single-disk failure,
your storage subsystem MUST continue to run -- albeit at degraded speed -- AND
your data is safe too.

The "R" in RAID stands for Redundant!


Another feature you may want to investigate is "hot-plug" capabilities:
if you want your CPU and main memory to continue humming along,
superior RAID subsystems permit you to replace a failed HDD
while the system is powered up and running. Then, a proper RAID
controller will incorporate the new drive into the RAID array
which had the failed drive, and "rebuild" the entire array
without skipping a beat.

This is not "theory" either; these features are now working daily
in practical enterprise situations.


While you're shopping around, check out the QuadraPack Q14
from Enhance Technology, Inc. Laptop hard drives in 2.5" form factor
are now available at 7,200 rpm, as are the enterprise-class "SAS"
drives that spin at 10,000 and 15,000 rpm.

http://www.enhance-tech.com/pr...ts/multidrive/q14.html

Although these 2.5" drives tend to be more expensive, per GB,
4 of them can fit into a single Q14, which comes with SAS-compatible
signal cables. And, the Q14 has a "hot plug" backplane too.

We tried out a Q14 for a prototype we built last December,
and that product is very well engineered and very well
manufactured.


Sincerely yours,
/s/ Paul Andrew Mitchell, Inventor and
Webmaster, Supreme Law Library

All Rights Reserved without Prejudice