installing promise raid controller with centos

watts3000 · 04-21-2007, 10:16 PM

I would like to know has anyone here used the promise fasttrack tx2000 with centos. The driver I downloaded stated that it will work with redhat 8 and 9. Also this is my firts tome trying to set up a raid card with linux what is the process like for installing drivers on linux?

Quakeboy02 · 04-21-2007, 10:27 PM

Unless you are dual booting Windows, I strongly suggest that you load the package mdadm and use that to configure your array. You shouldn't need to download any drivers unless you're using a 2.4 based kernel. If you're dual booting with Windows and you want to share data on the disk with Windows, post back and I'll walk you through that. You can also do a search on this site for FakeRaid.

watts3000 · 04-22-2007, 05:56 AM

I'm not sure I'm following you normally when I do raid controllers I hit control F at boot or whatever I need to get into the card. After that I configure my raid level through the dos like menu than boot windows hit F6 and put in the driver disk. It sounds like you are talking about configuring the raid after the system is up and running using the mdadm basically if I did that sounds like there would be know reason to install the promise controller at all.

Quakeboy02 · 04-22-2007, 01:56 PM

Quote:

It sounds like you are talking about configuring the raid after the system is up and running using the mdadm

Well, kinda yes and kinda no. During the partitioning section of install, you have to partition/configure the drives as an array. Then you install to that array.

Quote:

basically if I did that sounds like there would be know reason to install the promise controller at all.

Nope, pretty much not. I'm pretty sure that that driver you have is only for 2.4 kernels.

jschiwal · 04-22-2007, 02:08 PM

If it is an onboard promise controller, then I agree with Quakeboy2. Especially if it is an ATA raid controller.
You could be better off if you installed an extra ATA controller card and only use the master. Then install Linux software raid using your Fedora Cores partitioner program. You could probably also have a faster controller then what your motherboard supplies as well.

My previous desktop had a fasttrac controller. They only supply partial source, and the rest is in a precompiled object file. Only minor kernel version changes were possible.

Quakeboy02 · 04-22-2007, 02:36 PM

Quote:

jschiwal: You could be better off if you installed an extra ATA controller card and only use the master.

j, could you explain this comment for MY benefit?

quake

jschiwal · 04-22-2007, 05:09 PM

When the slave drive is accessed, the speed accessing the master will slow down.

There is also this quote from the mdadm software raid howto:

Quote:

It is very important, that you only use one IDE disk per IDE bus. Not only would two disks ruin the performance, but the failure of a disk often guarantees the failure of the bus, and therefore the failure of all disks on that bus. In a fault-tolerant RAID setup (RAID levels 1,4,5), the failure of one disk can be handled, but the failure of two disks (the two disks on the bus that fails due to the failure of the one disk) will render the array unusable. Also, when the master drive on a bus fails, the slave or the IDE controller may get awfully confused. One bus, one drive, that's the rule.

If you have the mdadm package installed, look for this howto in:
/usr/share/doc/packages/mdadm/Software-RAID.HOWTO-4.html

Quakeboy02 · 04-22-2007, 05:14 PM

Quote:

When the slave drive is accessed, the speed accessing the master will slow down.

I get that, but I don't understand the point in question. Why do you not want to use both master cables on the Promise controller?

jschiwal · 04-22-2007, 05:19 PM

No, I'm suggesting not using the Promise controller at all, but instead using IDE controllers.

Quakeboy02 · 04-22-2007, 05:34 PM

Quote:

No, I'm suggesting not using the Promise controller at all, but instead using IDE controllers.

Oh, OK. Now I understand. Sorry bout that. The Promise TX2000 is an IDE controller like any other, except that it has a bit of BIOS assist. Other than that, linux sees it as a Promise 20xxx IDE controller. I couldn't say whether the motherboard controller would be faster, but it's possible.

jschiwal · 04-23-2007, 01:57 AM

Quote:

Originally Posted by Quakeboy02

Oh, OK. Now I understand. Sorry bout that. The Promise TX2000 is an IDE controller like any other, except that it has a bit of BIOS assist. Other than that, linux sees it as a Promise 20xxx IDE controller. I couldn't say whether the motherboard controller would be faster, but it's possible.

If there is native kernel support for the card, then you could try using that.
I was saying the you may be able to get an IDE controller card that is faster than your onboard controller, not the other way around. This may be more likely to be true for an older motherboard or if the mobo cut corners on it's components.

When I first responded, I didn't realize that the promise controller was an addon card. However for IDE raid, there is little advantage over software raid. Especially if it is a cheap card.

I read a sata raid controller comparison on a website last week. The promise controller was the least expensive, but even though it was an add-on controller card, it used the cpu to handle checksum calculations instead of doing this on the card. The others performed these calculations on the cards.

IMHO, it is hard to beat a SCSI hot swap subsystem. Our old servers at work had them. They would feed video to SCSI decoder cards. These were old Pentium II servers. Because SCSI is an independent bus, it could work, whereas it wouldn't have worked using IDE drives. Also reseating a HD that is marked bad, or inserting a new drive is a lot more convenient than replacing an IDE HD.

Quakeboy02 · 04-24-2007, 07:34 PM

"However for IDE raid, there is little advantage over software raid."

Actually, there's no advantage at all on the performance side. To Linux, it's just another controller managed by the multi device support package. The utility of FakeRaid is if you want to either multi-boot Linux/Doze on a FakeRaid, or if you already have some Doze data on a FakeRaid.