View Full Version : RAID help

10-21-01, 11:33 PM
i want to use 3 HDs.

1 40gig all by itself on the primary ide channel.

2 30gig on the RAID channel.

now what do i set the jumpers to on the 2 30gig HDs? the single 40gig will be the master.

40gig - WD
30gig - Quantum

10-21-01, 11:56 PM
it has 2 raid channels doesnt it?set each drive to master and put one in each raid channel,am i missing something,do u want to have all those raided???or just the 2 and the third not on raid

10-22-01, 12:23 AM
Originally posted by m4a2t0t
it has 2 raid channels doesnt it?set each drive to master and put one in each raid channel,am i missing something,do u want to have all those raided???or just the 2 and the third not on raid

2 IDE channels
2 IDE RAID channels

the 40gig by itself on the primary IDE channel as the master, just a normal set up.

2 30gig HDs on 1 RAID channel.

do you use the RAID channels on your board? RAID takes 2 or more drives and basically combines it into a single fast drive.

ive asked if it was possible to run a single drive on the RAID channel and was told it was possible. that is not what i want to do thats a waste of space and totally defeats the purpose of having RAID controllers.

10-22-01, 12:57 AM
if you can, i would suggest having the 2 drives you would like to use for an array on 2 separate IDE RAID channels..... both set to master (each IDE channel, whether regular or RAID has room for 2 devices. one as a master and one as a slave). with IDEs inability to read and write both devices on a channel simultiniously, separating them between the RAID controller's 2 different channels would keep things as smooth and fast as possible.

the RAID controller is separate from the normal IDE controller as an identified device, so which one you boot from will easily be determined by your boot order as set in your system BIOS. so, in other words, the 40GB drive is really irrelevant when it comes to the array (just for argument's sake, the hdd on the regular IDE controller should be set as the master on the primary channel. even if you are not booting from it at present. just for future flexibility). if you dont have the extra IDE ribbon for the second hdd/IDE RAID channel, and they will be on the same channel then one should be set as master and the other as slave).

BTW, i am not sure as if you want to create a RAID 0 or 1 array, or if you want to just run the disks in span (or JBOD) mode. in either event, i would still configure the IDE devices as i mentioned above.

10-22-01, 02:54 AM

so 1 drive on each RAID channel, is that how it works?

this will give me a singular 60gig partition correct?

a bit confused...

10-22-01, 02:57 AM
that is correct. if you stripe the 2 30 giggers you will have 1 60GB RAID 0 array. you could still accomplish a RAID 0 array on one channel/ribbon (1 master 1 slave), but you run the risk of some performance loss. seperate the devices onto the 2 channels (each the master of its own IDE RAID channel).

10-22-01, 03:08 AM
if i were to add 2 more drives.

would i have 1 massive RAID 0 array or 2 seperate?

10-22-01, 03:21 AM
you can do either. you would just not be able to add the drives to the current array without losing all the data and rebuilding the array. if you were to add 2 more drives as an additional array (separate from the original array).

having a 4 device RAID 0 array will also be faster than a 2 drive RAID 0 array.... and twice as large.

keep in mind that the more drives you add to any single array will increase the chances of a single drive failure crashing the whole array. more drives = higher chances of total data loss. an array cannot be resurected unless you have some kind of mirroring (as in RAID 0+1 where the 0 is striping and 1 means mirroring). if you have 2 RAID 0 arrays on the same controller (on different channels), one array can be lost without affecting the other. in a RAID 0+1 array, however, you will need a mirror drive for every striped drive (2 striped and 2 mirrors).

10-22-01, 03:47 AM
that cleared some questions up and brought new ones up.

anyway thanks for the help man.

10-22-01, 04:03 AM
no sweat. do a search on "RAID definition" on your favorite search engine. there should be some good tables and explainations of what the different levels of RAID there are. there's many, many different levels of RAID. regular consumer-grade IDE RAID controllers only usually offer RAID 0, 1 and 0+1 (and span, or JBOD which isnt an array). once you understand how a RAID controller divides up the reads and writes between devices/drives, its fairly easy to understand the different levels.

there are commercial-grade IDE-RAID controllers which support RAID 5 and up, but here you are getting into high-end technology which really has no clear use in a desktop system.

whatever the case, you will like it. :)