Real Hardware RAID

Limit · n00b Joined: 20 Jan 2005 Posts: 15 Location: Russia

Good day to all.
I need а ATA RAID controller for gentoo-2.6.8-r3. It must be a real hardware RAID. I have about 500$. What can I buy for this money?

2K_amd64 · Posted: Thu Jan 20, 2005 5:32 pm Post subject:

I`ve bought 2 Highpoint RocketRAID 1820 for that situation. it has 8 sata channels, hw raid, lets you do raid10. price is 450 USD in Turkey. It has drivers for amd64 too, with source codes.

BUT

as I posted, I didn`t have any trouble on tyan s2886 dual opteron, I`m down on Intel motherboards with that card/driver.

I`d/I`ll not buy any special hardware anymore, if I can`t see it on "make menuconfig".

Highpoint RocketRAID works fine, if you can get it working.

Recomendation : Buy something what has native kernel support.

There is a nice howto or doc as far as I remember on sata raids (pointing which one is hardware and which one is not). Consider browsing www.tldp.org or google around for that document.

2K

2K_amd64 · Posted: Thu Jan 20, 2005 5:34 pm Post subject:

with a special adapter, you can use standart IDE disks in SATA raid arrays

Limit · n00b Joined: 20 Jan 2005 Posts: 15 Location: Russia

Thanks alot! I foget to say that I need RAID0, sorry.
My system are based on KT266A Chaintech 7VJDA

and I need RAID0 ATA controller. RAID 10 is cood, but I have no need in such abilities.
What else can you advice?

drescherjm · Posted: Thu Jan 20, 2005 8:11 pm Post subject:

I do not know of a single raid controller that does not have raid 0 so you can buy that one provided there is a linux driver.

[EDIT]
Oh.. I see he said there was a driver..
[/EDIT]
_________________
John

My gentoo overlay
Instructons for overlay

drescherjm · Posted: Thu Jan 20, 2005 8:39 pm Post subject:

Limit · n00b Joined: 20 Jan 2005 Posts: 15 Location: Russia

drescherjm · Posted: Wed Jan 26, 2005 4:34 am Post subject:

I asked that because there is very little if any performance advantage going from software raid 0 to hardware raid 0 because there is very little cpu time spent to stripe the data. In fact a hardware raid 0 controller may actually be slower than software raid 0 because the cpu on the card will most likely be significantly slower then the main cpu.
_________________
John

My gentoo overlay
Instructons for overlay

Limit · n00b Joined: 20 Jan 2005 Posts: 15 Location: Russia

I have two raid massive working on my copmuter. At the same time there are about 50 samba and 40 ftp connected clients. Moreover then working samba and ftp there are some different resources consumption programms. CPU 1700XP is not able to solve all tasks correctly. In last year I used Promise FastTrak100TX2 with kernel-2.4. and it worked excellent! In 2.6 that controller don't support like hardware raid, only like simple IDE-controller (or I simply don't now how to make it work in RAID-mode!) Thats why I decide to buy hardware raid. You are right that good processor better than raid-card, but I'll plane to change this computer in future, but not now. Please, help me to chose ATA RAID for 2.6.8-r3!

P.S Sorry my english =)

drescherjm · Posted: Fri Jan 28, 2005 10:18 pm Post subject:

FastTrak100TX2 is a software RAID solution. The card boots with a special bios and special raid driver that uses your cpu to do the raid. I gaurantee that the builtin linux software raid is at least as fast as the FastTrak100TX2 and you can use any regular ATA controller.
_________________
John

My gentoo overlay
Instructons for overlay

jschellhaass · Guru Joined: 20 Jan 2004 Posts: 341

If you need hardware RAID I would recommend a 3ware controller. True hardware RAID, works great under linux. Supports RAID 0,1,5 and 10.

jeff

Limit · n00b Joined: 20 Jan 2005 Posts: 15 Location: Russia

jschellhaass · Guru Joined: 20 Jan 2004 Posts: 341

What are you looking for? ATA or SATA? Howmany ports? They make a 4, 8 or 12 port controller in each type. I see they still also still have a 2 port controller that does RAID 0 or 1.

jeff

Limit · n00b Joined: 20 Jan 2005 Posts: 15 Location: Russia

jschellhaass · Guru Joined: 20 Jan 2004 Posts: 341

Then you will want the 7506-4LP (Low Profile) or 7506-8.

jeff

Limit · n00b Joined: 20 Jan 2005 Posts: 15 Location: Russia

Thank you very much jeff! It's that thing what i'm looking for!

localghost

cyrillic

Galahad · Tux's lil' helper Joined: 12 Feb 2003 Posts: 126

BIOS setting doesn't matter for controllers that don't do real hardware raid, meaning all the cheap ones.

silentplummet · n00b Joined: 14 Jun 2004 Posts: 58

Also consider that with a PCI RAID card (or cards) your I/O bandwidth is limited to that of the shared PCI bus. Theoretically you can get 66 MHz (66 mbit/s) out of that, but you can go ahead and subtract network, PCI sound, PCI video, etc....

Overclocking the PCI bus is rarely an option. You can pay lots of money to get a pci-e chipset which is faster but I've never personally seen one so I assume it's very rare.

I found a much more acceptable, cheaper, and faster solution is to software RAID-0 over two ATA-133 IDE channels and two SATA channels on the FSB frequency. This probably results in a bandwidth limitation higher than my four drives could ever match.

Edit: note that this solution also provides better redundancy in RAID-5 and RAID-1 modes because arrays are shared across different physical devices and channels. If your single PCI card bites the dust, that means all your drives are simultaneously going down. Not an option in a production environment.

The only reason to get a PCI solution these days is for a battery-backed write cache. But that too is becoming irrelevant with the growing prevalence of UPS systems.

Edit 2: If you're desperate for a hardware solution, the only real option you have is to get a hardware unit which is external to the computer. They make great networked and firewire arrays by which you can avoid the bandwidth problems of the PCI bus and get real features like physical hardware security (lock + key), and avoiding all the dangers of having some stupid WinXP or Gentoo box go down and take your whole office down with it.

Limit · n00b Joined: 20 Jan 2005 Posts: 15 Location: Russia

Good day to all. I'm very thank you for your advices.

Now I'm have a new idea: what about external storage?
It must:

1)Connect via 1Gb ethernet
2)SATA/SATA 2 disks
3) ~ 1500$ without disks

I know that better solution will be storage with SCSI+FiberChannel but it's cost too much for me.

And at last, what new RAID-card do you use/or can recomend to use?

jsnorman · Tux's lil' helper Joined: 24 Feb 2005 Posts: 131

Limit · n00b Joined: 20 Jan 2005 Posts: 15 Location: Russia

And what about external storage? Does anyone can help ?

jschellhaass · Guru Joined: 20 Jan 2004 Posts: 341

I think you will problems meeting that price point. Coraid (http://www.coraid.com) has a 4 disk unit for $2k. These systems use ATA over ethernet.

jeff

schwicky · Posted: Fri Aug 26, 2005 3:57 pm Post subject: