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View Full Version : Arranging 4 devices on 2 IDE controllers (G4)



dmunter
05-21-2007, 01:12 PM
Gurus,

I'm upgrading my G4 (QS 2002) and have a question about connecting my ATA devices. I have two 40GB drives that will be a mirrored RAID set (boot disk), a 250GB drive, and a CD-RW drive. Here are my options for arranging these devices:

Set the 40 GB drives as primary master and slave, set CD-RW as secondary master, and 120GB as secondary slave. This would require a new, long (36") cable.
Set the 40 GB drives as primary and secondary master, set CD-RW as primary slave, and 120GB as secondary slave.
Set the CD-RW drive as primary master, 120GB as primary slave, and 40GB drives as secondary master and slave.

So what's the lesser of three evils: long IDE cable, RAID1 across two IDE controllers, or non-boot drive as primary master? Should I also try to keep the CD-RW as secondary master?

Thanks for your advice!

Dan

ricks
05-21-2007, 01:22 PM
None of the solutions is very good in this case.

My first thought is that 40 GB ATA drives are going to be old and slow. Not a big deal, but something to keep in mind.

Next, you never ever want to make a RAID with 2 drives that are Master and SLave on the same channel. This is because of the nature of an ATA channel. Only one drive can be accessed at a time on a single ATA cable, so a RAID with 2 drives no longer works by simultaneously accessing both drives, instead those drives alternate access. This defeats the purpose of the RAID and slows things to even more of a crawl.

Second scenario, using the optical ATA bus for one of the mirror drives is not very good either. That bus is half the speed of the hard drive bus. And the hard drive ATA66 bus by todays standards is already slow. 2 drives in a mirror on different speed buses will slow everything again to a crawl.

I am not much a fan of mirrors anyway. It doesn't do much good. Better to use an application to make the backup and avoid the issue. A mirror's weakness is its instantness. If you corrupt the main drive you instantly copy the corruption to the mirror. Not all that useful.

Rick

TZ
05-21-2007, 02:22 PM
Option 3: invest in Serial ATA controller and drive(s).

Option 4: With ATA on QS/2002 - one drive per bus. Luckily, that machine has large 48-bit LBA support so you shouldn't be limited to 128GB if you want. Pick up 320GB ATA drive.