To Preben:
Thanks for your response and patience. The Abit board does permit JBOD; but
it does not provide RAID 5 as you have noted. When I asked about what
appeared to be a contradiction between what you suggested and what the ABIT
manual said I did not realize that there was a RAID 5 and that this was what
you were referring to. I apologize for my ignorance; but I am not sorry I
asked. Out of my asking, I learned about RAID 5, which I would not have
known about if I did not raise my question about the apparent contradiction.
To all who have posted on the subject of RAID:
Thank you; it has been an education. I have a few additional questions that
I need to be educated on and would appreciate any information that you could
provide me.
(1) If one sets up a RAID 0 (striping)with two 60GB disks, must each hard
drive be the master on a separate IDE channel or can they be set up as
master-slave on the same IDE channel?
(2) If one sets up a RAID 0 (striping)with two 60GB disks under WIN 98, can
one establish partitions for the array or must it be a single partition? In
formatting the drives to be used in a RAID array, how does one format each
of the disks with Fdisk (each disk being a brand new disk) with respect to
partitions?
(3)If one sets up a RAID 0 (striping)with two 60GB disks under WIN 98, can
one use utilities such as ScanDisk and Disk Defragmenter on the RAID array,
on individual hard drive disks in the array, or - if logical partitions are
usable with the array or disks in the array - on the partitions?
If this is getting to OT for the list, you can email me privately.
-----Original Message-----
From: owner-filmscanners@halftone.co.uk
[mailto:owner-filmscanners@halftone.co.uk]On Behalf Of Preben Kristensen
Sent: Sunday, November 11, 2001 3:53 PM
To: filmscanners@halftone.co.uk
Subject: Re: filmscanners: Best solution for HD and images
Hi Laurie,
You basically got it right:
Raid 0 or striping is putting two or more harddisks together into one bigger
disk. The Raid controller and software then divides say a 55 MB file in two
or more parts and writes them to the disks simultaneously. This is reversed
for reading files. The pros are great speed. The cons: if one disk goes -
all data on all the disks in the array is lost as well...
Raid 1 or mirroring, as you said, is just an automatic backup of one disk to
another disk... great security, but slow.
When you combine the two you get Raid 0/1 or 10 which is data is written to
several disks simultaneously and backed up automatically on a similar number
of disk. Therefore the smallest number of disks in a Raid 10 is 4; 2 Raid 0
and two Raid 1 combined.
JBOD is just a cluster of disks acting as one big disk - slow to write and
no security.
Raid 5 is like Raid 0. It writes to a number of disks simultaneously - but
somehow it distributes at the same time information on all the disks - that
makes it possible to recreate data should you loose one of the disks. In
that case you insert a fresh harddisk and the data belonging there will be
recreated. This is what I referred to as "payment for Raid 5 data security":
you loose the capacity of the equivalent to one harddisk in an Raid 5 array
of four disks. Ie: instead of say, 400 GB, which you would have available in
a Raid 0 or 200GB in a Raid 1, you get 300GB available in a Raid 5.
Because it needs to write this extra information to the disks, Raid 5 is
slower than Raid 0, but your data is relatively secure. Unless, of course,
you loose two harddisks at the same time from the same array. :-)
The Abit KG7 Raid does not offer you the choice of Raid 5. Only 0,1 or 10
and possibly JBOD - and AFAIK nor does any of the other motherboard built-in
Raid solutions.
There are other and much more complicated, secure AND expensive versions of
Raid. The Adaptec Website gives a very good overview: www.adaptec.com .
greetings Preben
----- Original Message -----
From: "LAURIE SOLOMON" <LAURIE@ADVANCENET.NET>
To: <filmscanners@halftone.co.uk>
Sent: Sunday, November 11, 2001 7:53 PM
Subject: RE: filmscanners: Best solution for HD and images
> Preben,
> Since you seem to be knowledgeable about IDE RAID matters, I wish to make
> use of your knowledge as a resource even if it is OT for this list. I
> recently bought an ABIT motherboard with RAID. The manual is not very
clear
> as tot he difference between RAID 0 (striping) and what it does versus
JBOD
> (spanning). I understand what RAID 1 (mirroring) is and how it works; but
I
> really do not understand how RAID 0 works or what parallel operation of
the
> two drives on the channel means and entails.
>
> While it may be different for third party RAID controllers, the manual for
> the RAID controller on the ABIT KG7-RAID motherboard says that you need 4
> drives to use RAID 0+1 and that the second pair duplicate the first pair.
> This appears to contradict your point concerning "You "pay" the
equivalent
> of one drive i.e.. - in this case - 100 GB for the security of your data,
> but you end up with a 300 GB drive array." If I ma reading the manual
> correctly, at least on the ABIT RAID, you would have 200GB of original
data
> storage and 200GB duplicate mirror backup protection under the RAID 0+1
> setup - especially if you follow their advice of using same size, make,
and
> model of hard drive in the array. Could you comment on this in a way so
as
> to add some clarification for a novice to RAID arrays.
>
>
> -----Original Message-----
> From: owner-filmscanners@halftone.co.uk
> [mailto:owner-filmscanners@halftone.co.uk]On Behalf Of Preben Kristensen
> Sent: Sunday, November 11, 2001 5:35 AM
> To: filmscanners@halftone.co.uk
> Subject: Re: filmscanners: Best solution for HD and images
>
>
> IMO the best price/performance/data safety setup is IDE Raid 5. If you buy
a
> Ide Raid 5 card (Adaptec makes a good one: 2400A, which sells for around
300
> US) you can then connect, say four IDE 100GB drives and get an array which
> is very fast AND fairly fault tolerant. You "pay" the equivalent of one
> drive ie. - in this case - 100 GB for the security of your data, but you
end
> up with a 300 GB drive array and the ability to swap/hotswap a drive and
> rebuild the array should one of the drives fail.
>
> Also, by using UDMA/100 5400 instead of 7200 drives you get a slightly
> slover performance, but you gain by having much lower temperatures and
much
> lower noise levels.
>
> Such a Raid 5 system would cost around 1300 US (depending where you buy)
for
> 300 GB, but your data is much more secure than the simpler and cheaper
Raid
> 0.
>
> Lastly, these stand alone Raid cards - unlike raid solutions on
> motherbords - have their own processors on board which takes over all the
> hard work, freeing up your system processor.
>
> Greetings Preben
>
>
> ----- Original Message -----
> From: "James Grove" <jpgrove@blueyonder.co.uk>
> To: <filmscanners@halftone.co.uk>
> Sent: Sunday, November 11, 2001 9:46 AM
> Subject: RE: filmscanners: Best solution for HD and images
>
>
> > I have just ordered a 60 Gig Maxtor ATA 100 drive (ATA 133 is also
> > available) I have done this because it is far cheaper than buying
> > another 36 gig drive to go on my U160 SCSI channel. I can get the Maxtor
> > drives for around 60 UK pounds, which means I could buy 4 of these IDE
> > drives for the same price as a Quantum U160 36gig drive!
> >
> > One thing to remember about Ide if you decide to give the drive a
> > beasting is to cool it with a slim cooler.
> >
> > --
> > James Grove
> > james@jamesgrove.co.uk
> > www.jamesgrove.co.uk
> > www.mountain-photos.co.uk
> > ICQ 99737573
> >
> > -----Original Message-----
> > From: owner-filmscanners@halftone.co.uk
> > [mailto:owner-filmscanners@halftone.co.uk] On Behalf Of Ezio c/o TIN
> > Sent: 10 November 2001 21:18
> > To: filmscanners@halftone.co.uk
> > Subject: Re: filmscanners: Best solution for HD and images
> >
> >
> > I would recommend to buy a U-160 SCSI ... from e-bay ... I have just
> > done this to integrate the other 3 U-160 I have and I have bought for
> > 102US $ a 18GB IBM 10000 rpm brand new under warranty. A 36GB 10000rpm
> > also IBM U-160 is rated for 170 US $ ...
> >
> > Sincerely.
> >
> > Ezio
> >
> > www.lucenti.com e-photography site
> >
> >
> > ----- Original Message -----
> > From: "Andrea de Polo" <andrea@alinari.it>
> > To: <filmscanners@halftone.co.uk>
> > Sent: Saturday, November 10, 2001 4:53 PM
> > Subject: filmscanners: Best solution for HD and images
> >
> >
> > > Hello,
> > >
> > > I have a CreoScitex scanner with attached a, Apple G4 Silver 733 with
> > > OS
> > 9.2.1 and 1GB of ram; I noticed that the internal HD is a slow 5400rpm
> > UltraAta HD; question: since I work only with Photoshop and my images
> > are about 60mb in size and I just have to open and save them during the
> > day (we process about 200 images/day), I was wondering what is the best
> > and effective way to speed up my work: buy a scsi external HD 10.000rpm
> > (total cost about 650 UK pounds), OR buy an internal UltraAta 7200 rpm
> > (total cost about 250 UK pounds) ???
> > >
> > > Again, we just have to open, retouch and than save our 40mb images,
> > > but
> > currently I am noticing that is taking a bit to access the HD.
> > >
> > > Thanks to give me your best solution for time/money issue. Andrea
> > > --
> > > ------------------------------------------------
> > > Fratelli Alinari Photo Archives and Museum
> > >
> > > The world's oldest picture library
> > > tel: +39-055-2395201
> > > gsm: +39-347-4883223
> > > fax: +39-055-2382857
> > > ------------------------------------------------
> > >
> >
> >
> >
>
>
