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Hardware IDE/SCSI RAID for Windows 2000 Servers?
reezle asks: "Mostly I was wondering what other sysadmins have been doing for Mirroring or RAID-5 in their w.2000 servers. I really don't like the M$ 'Enhanced' disks that allow for RAID, since I've actually lost a volume during the conversion from 'basic' to 'enhanced', and also I worry that I will get locked out of the volume if the OS goes belly-up on me. There is also the idea that software RAID is much slower, but it's cheap, and so are some of my customers. What kinds of solutions are being used successfuly? What kind of recovery nightmares have people run into? Is IDE RAID ready for the real-world server market yet?"
Seriously, Ask Slashdot question for this??
Toms Hardware IDE RAID review
IDE RAID without hardware
Exercise left up to reader: Finding SCSI RAID reviews
You know, I have seen lots of people say the exact same things as you. "IDE is so bad! Never use it!" "Use brand $x, it's the only REAL brand!" and overall, "Spend more money than you want to"
I'd like to respond in general to these things.
#1) IDE bad SCSI good.
The most common argument I hear is because of CPU resources. Now let's think about this. We'll go with the largest drive that each interface has. SCSI: 181GB @ @1000 IDE: 160GB @ $222 That is a price difference of almost $800 for $800, you can buy yourself TWO intel 2.4GHz processors. So if you arn't already running the fastest processor out there, you'd be better off (price-wise) getting IDE and purchasing a faster processor (or two, or whatever) This result is even more valid if you have more drives. (bigger savings) Quality of the drives? In many cases, they are the exact same drive with different electronics attached to them. The quality is the same. Also, there are IDE raid cards that have their own CPU. But you can just do software raid with the faster CPU. BTW, people: RAID does NOT improve performance. It hurts it. Read some benchmarks if you don't believe.
#2) ALWAYS buy the best you can afford.
I've got 4 servers that were the top of the line, most reliable hardware that are 5 years old. They are all working just fine. They cost $8k each back then. I've also got about 10 desktop computers flipped on their side, with 'server' written on them in crayon. They were about $2k each. They all still run just fine. If we had purchased all of them as desktops, I could have paid myself $24k extra. That money was wasted. Sometimes, (very seldom) it pays to buy the best. But if something is redundant anyway, get cheap! If it breaks, replace it. You've still saved the money. If it can be down, just keep it backed up, and buy cheap. You'll save money (a LOT of money) in the long term.
My basic idea here is that spending more money isn't always the best thing to do. Yeah, it's a lot more fun to play with a new Sun220R than a used P450 desktop from "Mikes Computers" but with a $10k price difference, there needs to be some VERY good reason to buy the expensive stuff.
Nathan Brazil?
As an interface, the difference between SCSI and IDE is small. Yes, Scsi has a few more controllability and asynchronous features, but these are not a big deal. The difference is that the manufacturesers use Scsi is a marker for a generally higher level of build quality and testing. Just as PCs marketed as servers are built better than desktop workstations, SCSI drives are simply better built than IDE ones. The price difference is not the trivial/zero cost of the different interface, it is better bearings, stronger actuators, more rigid cases, bigger buffer rams, cleverer firmware, extra levels of ECC, more vibration testing and so on. Check the MTBF figures - when I last looked, SCSI drives had 5 times the MTBF of comparable IDE drives from the same manufacturer. Basically, IDE is designed down to minimum cost for the cutthroat desktop/home market, while Scsi is designed up to beat the competition in the less price sensitive server market. [Most of this derived from talking to the tech support of a major disk manufacturer]
Which means that if you really, really, want your data to stay there, the delta of SCSI is probably worth it. OTOH, I would go for Raid-ed IDE before non-Raide-ed SCSI - drives fail, even the best.
There is no technical reason why IDE cannot be made host-swap - but not in an ordinary PC case. You need a mounting enclosure designed to make/break contacts in the right order, and a controller designed for hot swap. These cost money, and people tend to put that money alongside the premium features already in Scsi rather that the minimum-cost IDE.
Consciousness is an illusion caused by an excess of self consciousness.