[Ham-Computers] RE: Multiple drives, is there a way to . . .

[Philip, KO6BB]

Hi Aaron,

Thank you for the information.  Yes, my motherboard does support several 
different RAID options, though the one time I tried to implement it, I never 
got it working.  Think I was having problems getting XP to load the drivers 
on a fresh XP Pro install.

Like I said, the machine has the 80 and 500 GB internal drives (and I have 
spare 80 & 320GB internal drives too).  So that's fine.

It appears that the 'most' economical way to go is to purchase either an 
external case or a hotswap drawer for the 320GB SATA drive and use that to 
augment the external 320GB drive.  Though it hasn't been a problem here, to 
prevent the possibility of virus contamination of the archive drives, I want 
to be able to keep the external or swappable drives effectively turned off 
EXCEPT when doing the actual data backups.

That would be the most economical, setting up an external RAID array with an 
external controller would be the most expensive.  It appears the best 
compromise will be to just bite the bullet and buy a bigger external drive. 
Then I'd have the two 320 GB (internal SATA and External Firewire/USB) as 
drives to fall back on in the event I need still 'more' room ;-)

The need for growth is starting to slack off as there are fewer and fewer 
OTR series that I don't already have.  Most of the present "file-size 
growth" is in replacing earlier "LQ" (low quality/low bitrate) files with 
newer HQ (High Bitrate) encodes being offered by some of the OTR groups. 
Example: replacing older 32 Bitrate files with "denoised" or re-encoded 
128-256 bitrate ones.  The act of encoding a file is the process where an 
original transcription disk or tape is played and recorded to MP3 format. 
For awhile, to save disk space and put off buying another drive, I reduced 
the bitrate of many of my recordings.  Bad idea!

And to think, I can remember when I paid "big bux" for a HUGE 40MB drive for 
my 386 ;-)

73 de Phil,  KO6BB
http://www.geocities.com/ko6bb/index.html
http://ko6bb.multiply.com/

DX begins at the noise floor!
RADIOS: Yaesu FT-2000, FT-8800, FT-1802, FT-60.
Merced, Central California, 37.3N 120.48W  CM97sh


----- Original Message ----- 

Hi Phil (et al),

Yes, it is possible to do what you're describing via RAID-0 (RAID zero). 
RAID-0 is truly a misnomer as there is no redundancy, but it's a RAID form 
not the less.  Basically, RAID-0 is spanning - the data "spans" across the 
drives, so if you have two 200GB drives, the RAID-0 volume will show up as a 
single 400GB volume.  Three 200GB drives will make a 600GB RAID-0 volume and 
so on.  RAID-0 is the fastest of all RAID types as there is no checksum 
calculations nor redundant writes.

Typical RAID arrays require drives of identical size.  if any drive is 
smaller, then the smallest drive size is used as the "base".  So if you have 
a 200GB and a 250GB drive, then both will be treated as 200GB each and the 
RAID-0 volume will be 400GB in size.  An exception is if the RAID controller 
supports "JBOD" (Just a Bunch Of Disks).  In JBOD, the full capacity of each 
drive is used, so with the same example just mentioned, the JBOD volume size 
would be 450GB.


*** DANGER, WILL ROBINSON, DANGER! ***

RAID-0 (and JBOD) comes with a risk - if any drive in the array fails, then 
the data in the entire array is lost.  So the recommendation for most is to 
use RAID-0 only for temporal storage - not archives.  An example would be a 
scratch drive for video editing or for a PVR/Tivo.  Another example is a 
hard core gamer who wants the absolute shortest "load time" when playing 
games (to be the first to "jump in" a game level).  So be aware of this 
limitation of RAID-0/JBOD - make backups of all data you want to permanently 
store if it's on a RAID-0/JBOD array.


Depending on your system's motherboard, it may already have a RAID 
controller built-in (many do these days).  If so, you may only need to 
attach the drives to the RAID controller and enable RAID functionality. 
NOTE: you'll need to backup the data on the original drives first as once 
the RAID volume is created, everything on the drives is wiped when the RAID 
volume is created.  You can also add an inexpensive RAID controller for 
under $50 - these and most motherboard-based RAID controllers utilize the 
PC's CPU for much of the RAID functionality.  Higher priced RAID controllers 
include their own CPU's to take the burden off the PC.

There are also external USB/Firewire/eSATA enclosures out there that will 
create the RAID-0/JBOD volume for you.  Most of these also support RAID-1 
(mirroring) and possibly RAID-5 (striped parity)  One of the most innovative 
is the "Drobo" (http://www.drobo.com), but it's also one of the most 
expensive - many great reviews and designed to be very simple to operate and 
includes some proprietary data protection.

So, Phil, going by your description(s), it sounds like you need an "archive" 
which would eliminate RAID-0 as a possibility.  An exception is if you have 
a way of backing up the RAID-0 array.  My suggestion is to buy a 750GB or 
1TB drive (about $170 & $250, respectively) and not consider RAID-0.  Or, 
buy smaller drives and catalog by drive - each drive has a genre/program 
type/etc.  You may also want to consider using a desktop search engine like 
Google Desktop to assist with searches - Google Desktop builds it's database 
in the background and searches are fairly quick.  Never really used it as I 
don't have a large library, but I know people who love it.

One other alternative...build a RAID-5 array.  This is redundant, but 
requires at least 3 drives of the same size (smallest size drive rule 
applies if they're not the same size).  You lose the capacity of one drive, 
but the array is redundant - if one drive fails, the array itself still 
works and you can replace that drive and have the array rebuild itself.  So 
if you have 3 200GB drives, the RAID-5 capacity is 400GB.  If you have 5 
200GB drives, the RAID-5 capacity is 800GB.  With some RAID controllers, you 
can even add a second redundant drive (sometimes called RAID-6) so if two 
drives fail at the same time, the volume is still usable.  RAID-5 is most 
commonly found in data centers, sometimes combined with RAID-1 (mirroring) 
to form RAID 5/1 - this requires twice as many drives, so it's only used on 
"mission critical" data.  If you have an old PC laying around, setup a 
simple Linux server with a RAID-5 volume.

BTW, I'm in a similar boat as you - my PVR has 800GB of TV shows on a 
2-drive RAID-0 array that need to be archived - slowly putting them onto 
DVD's now.  And, with the new High-Def formats, I need to reconsider exactly 
how I'm going to handle 8GB files (1 hour of HDTV).

73,

  - Aaron, NN6O