SCSI RAID Question

[mikeasa]

I am designing a "low-end" server to sell to our customer base. We already offer a dual P4 Xeon server on our "high end". The "low-end" will have dual Athlon MP 2200+ CPUs on a Tyan K7X motherboard. The motherboard is the version with U160 SCSI built-in. Initially, we will be using the on-board SCSI for a Seagate 20/40GB tape drive that we sell with these systems. We are offering dual Western Digital 80GB 8MB cache hard drives in RAID 1 on a 3Ware Escalade 7210 IDE RAID card as the "low-end" hard drive option for this server. The SQL database for my company's software application will be housed on this server. The server will usually be a domain controller as well. The typical number of users on one of these servers will be from 5-20. They will be running Windows 2000 Server with 1GB PC2100 DDR RAM standard.

My question is: What is the best SCSI RAID card to offer as an alternative to the IDE RAID on this machine? I am looking at Adaptec specifically. I am not well versed on the performance differences between zero channel, single channel, and dual channel RAID cards. I know that there is a significant cost increase between each type.

What are your opinions on which RAID card to go with and what kind of performance differences can I expect between these cards? Also, what kind of performance difference do you think I would see between the above IDE RAID setup and the SCSI ones?

Thank you in advance for your responses!

 

[Magicthyse]

IMHO, SCSI in terms of value only becomes relevant when working with RAID 5 setups. With a RAID 1, a dual-channel ATA100/133 IDE hardware RAID adaptor should offer performance very close to - if not better than - a reasonable single-channel U160 SCSI adaptor offering hardware RAID - for a fraction of the price given a two-drive setup.

Since we're a Compaq/HP dealer, you know what and how we sell 😀 - For even low-end apps, we'd offer something from the NetRAID range.

 

[Pariah]

With SCSI I wouldn't bother with RAID 1. SCSI is inherently more reliable than IDE, and if there is a tape backup drive included, data reliability will be fine. A single highend SCSI drive will handle significantly more I/O's than an IDE RAID 1 setup. The additional cost of a RAID controller is not balanced out by any gained benefits to the user. If RAID 1 is mandatory, the built in mirroring in Win2K will perform just as well as a RAID controller, though be slightly more limited features wise.

There are no zero channel RAID capable AMD boards so you can leave that option out. The difference between single and dual channel is exactly what it sounds like. One has a single channel (cable) the other 2. The second channel allows an additional 15 devices to be connected and doubles the theoretical throughput of the card. For a 2 drive RAID 1 array, there is no reason to go dual channel. Performance of all 3 solutions would be basically identical.

 

[mikeasa]

Originally posted by: Pariah
With SCSI I wouldn't bother with RAID 1. SCSI is inherently more reliable than IDE, and if there is a tape backup drive included, data reliability will be fine. A single highend SCSI drive will handle significantly more I/O's than an IDE RAID 1 setup. The additional cost of a RAID controller is not balanced out by any gained benefits to the user. If RAID 1 is mandatory, the built in mirroring in Win2K will perform just as well as a RAID controller, though be slightly more limited features wise.

There are no zero channel RAID capable AMD boards so you can leave that option out. The difference between single and dual channel is exactly what it sounds like. One has a single channel (cable) the other 2. The second channel allows an additional 15 devices to be connected and doubles the theoretical throughput of the card. For a 2 drive RAID 1 array, there is no reason to go dual channel. Performance of all 3 solutions would be basically identical.

Actually the S2468UGN model of the Tyan K7X does have support for the Adaptec Zero Channel RAID.
🙂