Raid Questions and system setup queries

[ronsandiego]

Hi All,
Obviously there are a lot of very sharp folks here who can give me good input. I have obtained a lot of great help from SysOpt forums in the past.

I am trying to learn all I can about Raid. Raid 1, 3 and 5 is my decision. I know all the basic theory stuff about RAID but need to make some purchasing decisions. (I have built 3 PCs lately, and have experience with home networks). I have 2 PCs which have AMD Xp1600 on KT7 266 RU mbs, 512 MB DDR, which have worked well. Have not used the Raid on these boards, and I have not personally installed a Raid system.

I will be setting up a Win2000 Server domain for a small business. Actually this will be an upgrade setup for them. They are now getting along using a Dell 800 MHz 128 mb RAM NT4.0 server, with an older computer for a backup server.

The business has about 30 clients which will be upgraded to Win2000 Pro. They also have a couple of Unix servers and some remote connections. The business is mostly engineering work.
They run about 4 printers, on a network with a Cisco Router hooked to the outside world, feeding two 24 port hubs.

I will use 2 Win2000 Server domain controllers. (I know a lot about Win2000 Server OS.) I will design and setup Active Directory to meet the needs of the business).

My main area of need here is RAID knowledge from experienced folks. I am reading about all the various RAID controller options, and hope folks here can steer me in the right direction and help me sift the wheat from the chaffe on this large topic.

For the Server hardware, I am currently am considering using something on the order of AMD xp1600 or better CPU on MSI KT3 Ultra MB, with at least 512 MB DDR RAM. I understand that this Mboard supports Raid1.

I want to set up some sort of RAID for redundancy for the stuff on their servers. (In addition to the normal daily and weekly backup procedures).

My plan would be to get at least 3 80 GB HDDs on each machine, with two used in perhaps a RAID 1 system. Now I am wondering about getting something that will permit RAID 3 or RAID 5. So have started reading about RAID Controllers.

I have read a lot of the threads on RAID on these boards.

My major questions are:
1) What are pros and cons to using the onboard RAID setups vs getting a Raid Controller?

2) What brand of Raid Controllers do people favor? Prices?

3) Talk to me about IDE vs SCSI RAID-- would like to go with IDE since it is cheaper.

4) Please comment on this product from Promise which uses SCSI I/F and then uses an external RAID system with IDE HDDs. see :

http://www.xbitlabs.com/storage/promise-ultratrak100-tx4/

5) I read on some thread here that the Win2000 OS should not be put on one of the participant RAID drives? Comments?

6) How much impact on the CPU usage will the RAID system bring to bear? Should I boost target CPU speed due to the presence of using RAID?

7) Are there significant differences in the impact on the CPU usage due to RAID using a MB RAID system, or a RAID system run via a Raid Controller.

8) comments welcome as to the organization of what best should be placed on the RAID system and what best should be put on another HD are welcomed.

9) Comments welcome as to my proposed server hardware, and anything else anyone can contribute.

Thanks in advance for all the help.

ronsandiego

[Midknyte]

You post is kinda long, so sorry if i miss something.

first, you wouldn't be using RAID3. RAID3 is striping with parity on a single drive. No one uses that version of RAID.

You would have your choice of RAID0-striping, RAID1-mirroring, or RAID5-striping with parity on all drives

If you are going to run a business server, you should consider getting a SCSI setup rather than IDE. SCSI performs much better in a network environment. Many servers come pre-built with scsi and windows 2000 preconfigured.

You'd want to use RAID5 in a business environment. If one drive goes down and you have hot swap, you can just pull the bad drive and pop in a new one with minimal time lost. Mirroring is ok, but the dual writing slows down the server. RAID5 gives you fault tolerance with less of a performance hit.

Onboard and PCI controllers make no difference at all. Both are still on the PCI bus. Onboard makes it easy, but if the controller goes bad, you gotta replace the whole board.

If you're going IDE, the promise is probably the best. If you're going SCSI, then Tekram and Adaptec are pretty good. Adaptec is kinda expensive, though.

If you have hardware raid, then you can put your system/boot partition on the raid. If you are doing software raid through windows 2k, then you cannot put the system/boot partition on anything, but a mirror.

SCSI systems would use a lot less CPU time.

I would check into getting a server from Dell or another prebuilt server. They give good tech support, especially if you're new to the game.

Dunno about that scsi IDE RAID thing. the bottleneck will still be the IDE, so it doesn't make much sense to do that. the scsi only connects the external box to the internal controller card and doesn't manage the hard drives. the IDE RAID controls the HDDs.

It really depends on the fault tolerance you need. If you have to be up 24/7, then RAID5 is the way to go. The stronger the fault tolerance, the more expensive it will be.

I'm tired now. I think I need a nap. :(

[jmichna]

The only thing I'd add to Midknyte's post is also consider 3Ware if you are still leaning toward IDE RAID. They make excellent, hi-performance IDE-RAID controllers. You would probably be interested in their model Escalade 7450, or more likely the Escalade 7850. Click here (http://www.3ware.com/products/escalade.asp) for info.
Regards,
jmichna

[BipolarBill]

3Ware = good stuff. Recommended.

[Midknyte]

Wow! That 3Ware stuff is pretty awesome for IDE. I'm still not totally sold since it lacks the disk error protection that scsi has, but it should be way cheaper for the capacity you get. Hotswap and everything. That's cool. :D

[lito pospos]

My major questions are:
1) What are pros and cons to using the onboard RAID setups vs getting a Raid Controller?

*On board raid it use your system processor additional usage while there is raid controller with processor on it and cache of 6mb,8mb,16mb,64,mb.124mb or higher and raid manages the drive independent of the host processor

*Early 90s raid controller technology they use 386/486 processor to speed up the processing, now a day they are using risc processor for better performance or may be Pentium base who know technology move ahead.

2) What brand of Raid Controllers do people favor? Prices?

* Symbios or Adaptec/DPT they are good player in the market. and price $$$$

3) Talk to me about IDE vs SCSI RAID-- would like to go with IDE since it is cheaper.

* Ide raid you can attach limited device only and built-in on board mostly it up to raid 1,0 there is a card that’s support up raid 5 plus hot spare and hot swap also, but in scsi raid per channel supporting up to 6 device and raid level 5,1,0,4 or plus hot swap and hot spare support if one drive fail your hot spare automatic take over the fail drive, hot swap you can replace the fail drive without shutting down the system

4) Please comment on this product from Promise which uses SCSI I/F and then uses an external RAID system with IDE HDDs. see :

http://www.xbitlabs.com/storage/pro...tratrak100-tx4/

*That’s ok for me how about tech support ?and price vs the branded one.

5) I read on some thread here that the Win2000 OS should not be put on one of the participant RAID drives? Comments?

*Who wrote? one of the lonely guy.
I use hardware raid 1 for my boot device and raid 5 for data or application plus one drive as hot spare.

6) How much impact on the CPU usage will the RAID system bring to bear? Should I boost target CPU speed due to the presence of using RAID?

*if you are using raid controller with processor on it plus high cache memory or accelerator it minimize the cpu usage or It almost forget your system processor .

7) Are there significant differences in the impact on the CPU usage due to RAID using a MB RAID system, or a RAID system run via a Raid Controller.

* It defend some on board raid w/o cache or memory cache is low that the time they add the other raid controller with high cache memory to utilize their system performance. Check 1,6


8) comments welcome as to the organization of what best should be placed on the RAID system and what best should be put on another HD are welcomed.

*raid 1 boot device and raid 5 plus hot spare, for SFT.

9) Comments welcome as to my proposed server hardware, and anything else anyone can contribute.

*server with system fault tolerant

multi processor
Redundant/hot plug power supply
Redundant/hot plug cooling fan
Hot plug PCI slot
Hot plug harddisk
Raid support 1,0.4,5 and hot spare

[BipolarBill]

Huh? I guess you could call that a soliloquy? ;)

[ronsandiego]

To all who replied. --
Thanks very much for the information.
--Ron

[matt50]

Hope this link could help abit more..

http://www.acnc.com/raid.html

As for mode.. better go for hardware SCSI raid/interface coz there will be lot of people accessing that storage. Furthermore it'll lessen the CPU usage on the system.

Cheers.