topic Re: Raid 1 w/2HD and 3rd HD not raid? in Disk Enclosures

Raid 1 w/2HD and 3rd HD not raid?

Dale Corrington — Thu, 15 Sep 2005 09:22:46 GMT

Can I configure an HP xw4300 with (3) 73GB scsi U320 drives as 2HD mirrored and the 3rd drive seperate storage? I would use the 3rd drive as a daily backup device since a tape drive for this user is not practical.

Re: Raid 1 w/2HD and 3rd HD not raid?

Steven Clementi — Thu, 15 Sep 2005 09:32:41 GMT

Dale:

I am not at all familiar with the xw line, but in the Proliant world, a Smart Array Controller would easily be able to fulfill your configuration. I would think any HP Array Controller would be able to do the same or similar, but can't say for sure as I never even seen an xw.

Steven

Re: Raid 1 w/2HD and 3rd HD not raid?

Dale Corrington — Thu, 15 Sep 2005 09:40:30 GMT

Maybe I shouldn't be in the array forum. It's a workstation with a "U320 single channel SCSI RAID controller" and 3 interal HD.

Re: Raid 1 w/2HD and 3rd HD not raid?

Steven Clementi — Thu, 15 Sep 2005 09:57:21 GMT

Running Windows? or Linux?

Software based RAID is doable in the manner you speak of as well.

Steven

Re: Raid 1 w/2HD and 3rd HD not raid?

Dale Corrington — Thu, 15 Sep 2005 10:09:18 GMT

Windows XP. I don't know that I want to go with a software raid. I haven't bought this yet, so I am open to other hardware solutions.

Re: Raid 1 w/2HD and 3rd HD not raid?

Steven Clementi — Thu, 15 Sep 2005 10:51:58 GMT

You can get an Array contrller for the workstation. Doesn't have to be a Smart Array, but a Smart Array would probably work.

Not sure how much need there is for a hardware based RAID solution in a workstation, but I am sure your asking about it since you have some concerns.

Steven

Re: Raid 1 w/2HD and 3rd HD not raid?

Uwe Zessin — Thu, 15 Sep 2005 11:24:28 GMT

From looking at the specifications, it looks like this 'SCSI RAID controller' (LSI 20320A-R) cannot do what you want:

http://h18000.www1.hp.com/products/quickspecs/11954_na/11954_na.HTML

- Supports a single RAID volume RAID 0, 1, or 1E
- Number of supported devices: Up to 15 SCSI devices
- Host bus transfer rate: Up to 1MB/s
- SCSI data transfer rate Up to 320MB/s per channel

(I'd call that a joke, not a RAID controller)

Re: Raid 1 w/2HD and 3rd HD not raid?

Dale Corrington — Thu, 15 Sep 2005 11:34:05 GMT

Thanks for the answer. To be fair, I am asking a bit much for a normal workstation. This card only cost $40 more to add the RAID.I guess I need a different solution for the daily backup and just get 2 HD with RAID1.

Re: Raid 1 w/2HD and 3rd HD not raid?

Uwe Zessin — Thu, 15 Sep 2005 11:45:40 GMT

Well, a RAID controller should really have a bit more flexibility if it supports up to 15 disk drives, but I might be asking a bit too much as well ;-)

I see that the xw4300 has an embedded SATA controller. From the description it sounds like it can't present a single disk either, but you might be able to trade a single SCSI disk against a RAID-1 pair of SATA drives for backups.

Now it is getting a bit tight in the system box as you need to use slots reserved for optical devices...

Re: Raid 1 w/2HD and 3rd HD not raid?

Ron Lawson_1 — Thu, 15 Sep 2005 23:44:26 GMT

I think that Host Bus transfer rate must be a typo -- it should be up to 1 GB/s (PCI-X 133MHz capable).

Re: Raid 1 w/2HD and 3rd HD not raid?

Uwe Zessin — Thu, 15 Sep 2005 23:59:15 GMT

I agree, although it is in at least two different specifications on the web - looks like a multiple cut&paste error.

Still, one RAID volume only is a joke to me.

Re: Raid 1 w/2HD and 3rd HD not raid?

Dale Corrington — Fri, 16 Sep 2005 09:43:52 GMT

I will do the RAID1 on 2HD and go with tape for daily backup. Thanks all.