4 channel ide raid, with RAID 5
I just bought an Epox 4PCA3+. It comes with a HPT 374 - 4 channel raid 0/1/5 controller, AND a separate SATA Raid controller.
I tried to set up the array with 2 Maxtor 120gb/8mb ata133's but it never worked...It showed the array proper, but I could never get windows to install successfully on it. I am guessing that my major goof was not partitioning the array into usable sizes (heh - I had a 240 gig part). RAID 0 is new to me, and that was a first attempt. I didn't know how the parity drive on a RAID 5 needed to compare size-wise with the other drives on the array. The only real way I feel safe using striping is in an array with parity.
Would I be better suited to use a couple of the Raptors in the SATA array instead? And is SATA like PATA in that only one master per channel? Can you even run more that one drive per channel? Or is it more like SCSI... with each drive having a degree of autonomy? I have a use for each of the Maxtor 120's if it would be better for me to use the Raptors...but I dunno...at 36 gig each, I would want like 3, and this is only a 2 channel controller. On the other hand, I could also use the Seagate "true serial" drives in a 120. If the latter, would I be better off to use 2 60's? Or would just partitioning the 120's be OK?
And can I go and ghost my current drive (no array at all), and then set up the array, and transfer the image? Or will I run into problems because the controller for the array wont be a part of the image...
Finally...how reliable is RAID 5? Should I not mess with it, and just keep a ghost image? If so, what drive image program is the most user friendly, and reliable?
I tried to set up the array with 2 Maxtor 120gb/8mb ata133's but it never worked...It showed the array proper, but I could never get windows to install successfully on it. I am guessing that my major goof was not partitioning the array into usable sizes (heh - I had a 240 gig part). RAID 0 is new to me, and that was a first attempt. I didn't know how the parity drive on a RAID 5 needed to compare size-wise with the other drives on the array. The only real way I feel safe using striping is in an array with parity.
Would I be better suited to use a couple of the Raptors in the SATA array instead? And is SATA like PATA in that only one master per channel? Can you even run more that one drive per channel? Or is it more like SCSI... with each drive having a degree of autonomy? I have a use for each of the Maxtor 120's if it would be better for me to use the Raptors...but I dunno...at 36 gig each, I would want like 3, and this is only a 2 channel controller. On the other hand, I could also use the Seagate "true serial" drives in a 120. If the latter, would I be better off to use 2 60's? Or would just partitioning the 120's be OK?
And can I go and ghost my current drive (no array at all), and then set up the array, and transfer the image? Or will I run into problems because the controller for the array wont be a part of the image...
Finally...how reliable is RAID 5? Should I not mess with it, and just keep a ghost image? If so, what drive image program is the most user friendly, and reliable?
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but if your gonna have all your sensitive data on it, i would say go raid 5 , minim. 3 drives required.
hope this helps.
The maxtors should of worked fine. Any more clues on why XP wouldn't install? You hit f6 to install drivers etc.... It can't tell the differance between true SATA and PATA with converters BUT some converters have problems with some drives?
You had so many questions I almost wish you had numbered them.
No there is no master slave in SATA but for example my maxtors did not like cables select hooked to my hpt 1540 sata which is a 4ch sata. Set them to master and you get one per channel.
With raid 5 you need a minimum of 3 drives and your write performance with 3 raided will almost equal on atto what a single drive hits on the second line when your raid-5 is maxing out. Sort like writing at the speed of a ide from 8 or ten years ago basicaly.
I run two 80 maxtors but I always cut mine up for reasons other then max sizes per partition but the largest one is 160mb and works fine if that helps at all. You want to carefuly try and match or be a close multiple of cluster size to stripe size. Try and use maybe 16k/16k for those drives as a starter. I would not image anything and restore to a raid-5. Build a raid-5 from scatch. This is nothing like raid-0.
If the problem was max drive size being exceeded the partioning would help but I am not sure from what you have posted if thats the case.
But for housekeeping reasons its better to keep swapfiles and temp files away from the OS anyway.
Tex
When I talked about the array I attempted, I should have mentioned that I was using 2 channels of the 4 channel HPT 374 IDE with 2 standard Maxtor 120's...not SATA. I was also trying to run RAID 0, not RAID 5.
(I was considering RAID 5 only for my second attempt)
My question should have been more pointed too: Since my board has both SATA, and the IDE (PATA?) controllers, should I forget about using the 2 120's that I have, and instead get 2 SATA's (purely for performance reasons)? And if I do that, then I can only use 2 drives, because of the need for them to run as master? In other words, using 10k Raptors, I would be limited to around 75 gig?
And what I meant about transferring an image, I meant with respect to RAID 0 (at this point RAID 5 is no longer a consideration). Can I SAFELY make a disk image from a single drive, and successfully transfer it to the array? I would like to be able to preserve the time that I have taken in compiling the contents of the current drive, by just 'pasting' it to the array - via image. I am not sure how that works though...wouldn't I have to have an OS installed somewhere in order to control the array during the image transfer?
Contrary to the message that this post may imply, I'm not really a dope...LOL...I just have a few "wires crossed" when it comes to this.
I had originally intended to install the OS on a 15k U160 drive, and then use the 2 120's in a RAID 0 for programs and speedy storage. But then I ran into a few issues that I wasnt sure how to resolve:
1. When I tried to boot to the OS with the IDE's plugged in, the machine wouldn't boot from the SCSI drive...it just told me there was no OS found. The only way I could get it to boot from the U160 drive, was to unplug the IDE's.
2. I was troubled by having to decide what to put where in order to make a surprise 'need-to-reformat-the-OS-drive' less painful. I wanted to be able to reformat that drive at any given time without having to be concerned with moving files I wanted to keep. I keep alot in My Docs...and I didn't know if that was easily moved to a drive separate from the Windows install.
I also wanted to utilize 4 partitions on the boot drive...1 with XP pro, 1 with ME ( for some programs that I have ), One with Win 2000 (Just for the sake of learning that OS), and one left for a Linux experiment. Everything worked fine with XP and 2000 or XP and ME, but when I tried to add the 3rd OS...it hiccupped.
So to make a long story longer... LOL j/k...I decided I was best suited to just get the machine running. That's when I decided on XP Pro as the OS, and was going to use the dual 120's for the 'boot drive' in RAID 0. Which didn't work either. the install just seemed to stop near the end. Tried it repeatedly...yes I f6'd. It just seemed sluggish, and then appeared to grind to a hault. From there I said hell with it, and just put everything on the one IDE drive.
So... here I am
So you used one of the 120gb's right? So you are not going to raid them or?
Exatly what boot options do you have in the bios? When you want to boot from the sata what do you select in the bios to boot from it? On my hpt374 I set it to "scsi" which as you may of found creates probs co-existing with other scsi controllers. Gets to sorta be a war over which bios shows first at boot as it usually wins. My hpt374 is a 1540 sata card and I can shuffle it around at times and get around the prob but yours is built in right?
Two sata drives may be marginaly faster then the two maxtors you have but not much. The raptors are a little faster but again... not a super amount. I have seen your drives raided on a sata controller and score better then some guys raptors but ... I have seen a couple raptor scores that were > 105.000 or so. But is it really worth the price performace versus available disk space you give up?
Let me know when you want to play with this again and lets give her another go.
Tex
Main PC has 2 x Seagate 7200 RPM/8M drives in RAID 0 with a 16k stripe size on an Abit IC7-G internal (not the SiS) Serial-ATA raid controller. The performance is blistering but if I lose a drive, I lose all the data.. which brings me to
Server has 8 x 200GB Maxtor 6Y200P0 7200RPM/8MB cache in a RAID 5 on a HPT404. The HPT37x RAID controllers all do XOR in software so that read/writer performance is miserable! If you do have one, upgrade the BIOS to at least 3.03, it makes the card slightly more bearable. Its there for storage and I backup the striped set to it
Now I would like to un-dirty Raid5's bad name in this post.
First, this post refers to hardware-assisted-software Raid5. The onboard raid controllers on many motherboards are software raid built into the firmware of a chip on the motherboard and performance is highly dependant on firmware version and driver version. This is sometimes but not all the time faster then true software raid. To my knowledge using software raid on one of the newer linux or *BSD kernels is sometimes faster then using an onboard highpoint or similar raid option.
Second, true hardware Raid5 costs $300+. A hardware Raid5 controller includes an onboard processor that does the calculations for parity bits. This onboard processor and the performance gains it achieves cannot even be compared to software raid5 or onboard raid5. Although hardware Raid5 will not perform as well as Raid0 it will easily perform almost as well or better then RAID0+1 on an onboard controller. Also, the performance of raid5 is partially dependent on how many drives you have in the array. It requires at least 3 drives but supports more in increments of 1, and each drive on a new channel adds a percentage of new bandwidth. I will happily put my 4 channel Raid5 array on my 64-bit PCI 3Ware card in my server, against any onboard Raid0+1 or onboard Raid5, dare I say Raid0…
I have 4 Seagate 7200.7 200GB SATA drives on a 3Ware Escalade 8506-8 as Raid5 and here are my hdparm results under Fedora Core 2
/dev/sda1:
Timing buffered disk reads: 100 MB in 0.94 seconds = 106.85 MB/sec
/dev/sda1:
Timing buffer-cache reads: 2832 MB in 2.00 seconds = 1414.09 MB/sec
But... the 3Ware card is $500