Should I use RAID for my server ?? or SCSI ??

[Superlac]

I am building a server..and I was wondering...about RAID. What's RAID and is it any good for my office server ??? I am thinking of running 147 gig SCSI hard drives...soo is RAID an option for me ?? and is it easy ??

thank you

[John Prophet]

lol, one thread is easier to follow than two. Personally I wouldnt worry about scsi unless you just absolutely need the 2-5% gain in speed it gives. With plain old easily available raid 1 on IDE drives you have a pretty good setup.

[PresterJohn]

using a scsi subsystem can give more than 2-5% throughput gain. it really depends on the types of files being accessed and the # of simultaneous reads/write requests occuring.

there are many different types of raid. do a google search to research which would work best for you.

in cases where raid is used for fault tolerance, raid 5 is superior to raid1 because less disk space is wasted. you will need a min. of 3 drives to implement raid5...the more drives you add the less waste occurs.

[Peter M]

3 to 5 percent? More like 30 to 50, my friend. If your server is actually running server tasks, that is.

"Servers" that twiddle their thumbs waiting for a bit of file system action from the two or three PCs connected to them, without having to run any database queries, web serving or such, will be bored enough to make it look like there is no performance gain in SCSI.
Sure, SCSI is expensive ... in initial purchase cost. Total cost of ownership is a different story, given the huge reliability and longevity delta between SCSI and IDE harddrives.

So if you want to do things right, use a SCSI RAID5. With a proper RAID card that has its own brain, rather than letting the main CPU do all the RAID work and waste a lot of I/O bandwidth at the same time.

[sechs]

So, exactly what is this server going to do?

[John Prophet]

what ya'll dont realize, is that I love to leave the door open for people to correct me, lol....which on this board I find out happens plenty enough.

The thought process that I actually went thru was more like "if he is asking whether or not he should use RIAD, a scsi raid 5 type setup would be too complicated to mess with"...that was my actual thinking. I just threw up a guestimation on the %...although Id like to see benchmarks with anything resembling 50% difference....maybe in certain specific tasks...but he hasnt even really said what it would be used for so I figured just general backup/ simple app serving.

Anyway, that was my thought process there if anyone cares..wasnt really trying to give some accurate benchmark...more like trying to dissuade someone from getting in over their head.

I sometimes forget the wrath of the "pro scsi" (or pro-mac, or pro-this or that crowds, lol)

JP

[thegladiatorgy]

I'd go for 2 WD Raptor 36GB RAID1 for the OS and Apps and
2 SATA Maxtor 160GB RAID1 for the files you'll be sharing.

Of course you're going to need a good SATA controller.

[Peter M]

John, the performance gap between IDE and SCSI opens wide as soon as multiple tasks need to be fulfilled. SCSI drives can take multiple read/write requests at the same time, and rearrange, sort and complete them in any order that lets the drive perform best - e.g. minimizing rotational latency by fetching the data first that spin by the head rack next.
IDE drives take only one command at a time, which implies an in-order completion with far less than optimal head movement and rotational latency.
That's why I said this is really going to show when the server has to get serious about its serving business.

Of course, SCSI HDDs must have a far more sophisticated and powerful firmware inside to achieve this. This development effort and brainpower is part of why SCSI HDDs are more expensive.

If you want to see numbers, go to www.storagereview.com, Performance Database, and look at the "Server DriveMark" numbers. The bestest IDE drives - WD's Raptor Series-II drives - cannot even keep up with SCSI drives from two years ago. Today's top notch SCSI drives are up to 80 percent faster.

[John Prophet]

yeah...but he aint said what it going to be used for yet! lol.

the word "server" is pretty varied in its usage...I mean, I totally agree, scsi rocks! no doubt....but if he is doing all the tech work himself, lol....IDE is a lil easier to deal with yes?

[Superlac]

Wow..thanks for quick resonnd guys...thank you so much...

Well let me explain my "server" usage more, so that you guys can help me out. Ok I am planning to build a server for my office to back up all of my patients data. I have 10 pc that I use for input my data to the future server. On the server I would probalby have 1 or 2 software running SQL queries so that the 10 pc would open the local software and open the data located on the server. With the data open on the 10 client pcs. I will change the data and update the data, then save it back to server.

So with that said..what would be best for me ?? Raid 0 +1 ?? That's the one that I just read about and understand a little bit of it. You guys have mentioned about RAID 5....what's the pro and cons about that ?? Please help me...I really need to setup this server...

P.S. I already have like 5 SCSI 146 HDDs. So I am thinking to running SCSI RAID b/c my data for my office is really important. Ohh I already have a LSI 160 mb/s 2 channels SCSI card...Can I use that card with this server ? or I have to buy a motherboard that has a built in SCSI and RAID ?? please help.... Or I can just use my LSI SCSI card and then buy a separate RAID card to do RAID ?????

Thank you in advance for your help,