[majesticmac]

bought 09/04 G5 dual 2.5 with 4.5ram/ 6800 ultra ddl/250gmaxtor & 400g Hitachi_FCP Studio

I want to build a RAID to edit uncompressed video and I am pretty ignorant about raids BUT I am reading about it everyday trying to learn what I need to do. I was planning on getting a enclosure and putting 4 x 400g Hitachi SATA. I have seen a PCI card that has 8 inputs on it externally, I wanted the option of expanding the Raid to 8 drives down the road.

Now I am reading about adding more inside the G5, I have read about hooking them up without a PCI card. Am I confused or is this possible. I would like to keep the price down and saving $$ on an enclosure and PCI card. I am a little overwhelmed with all the info. I would not like to use the optical drive space for xtra drives but I could use the rest of the box even if I can only add 3 drives instead of 4. I would use the 400g Hitachi I already have as part of the RAID. Any direction would be appreciated. I plan on buying a the first of the year.

[majesticmac]

I just called Maxconnect and asked them if I had to buy a PCI card to manage the raid and the answer is yes. I thought I read somewhere that you could plug them directly to a some original board inside the Mac, I think I just got confused.

[mduell]

You can fit a few more drives inside the G5 case with third party addons; 2 or 3 more in addition to the original 2.

External SATA arrays are easy. Get a PCI-X card that has 4-8 external ports (SATA or e.SATA), and then get some external enclosures. You can get enclosures that accept 4 drives and have just one cable back to the computer, but that limits speed greatly. I think you're better off with single or dual drive enclosures with a cable for each drive.

[OreoCookie]

Originally Posted by mduell

You can fit a few more drives inside the G5 case with third party addons; 2 or 3 more in addition to the original 2.

External SATA arrays are easy. Get a PCI-X card that has 4-8 external ports (SATA or e.SATA), and then get some external enclosures. You can get enclosures that accept 4 drives and have just one cable back to the computer, but that limits speed greatly. I think you're better off with single or dual drive enclosures with a cable for each drive.

Not necessarily. Some more advanced enclosures include the RAID functionality within the box. This way, you can plug in your RAID on any computer and you don't have to worry about software RAID and all this.

[mduell]

Originally Posted by OreoCookie

Not necessarily. Some more advanced enclosures include the RAID functionality within the box. This way, you can plug in your RAID on any computer and you don't have to worry about software RAID and all this.

True; they also cost $500-1500 (compared to $25/ea for single drive enclosures) and limit you to 150MBps aggregate (which may or may not be fast enough for the OP). Also the OP never mentioned a desire for portability, so the avoidance of software RAID may not be important.

[OreoCookie]

Originally Posted by mduell

True; they also cost $500-1500 (compared to $25/ea for single drive enclosures) and limit you to 150MBps aggregate (which may or may not be fast enough for the OP). Also the OP never mentioned a desire for portability, so the avoidance of software RAID may not be important.

True. I was thinking about security rather than portability. If you have a non-trivial RAID-level, the enclosure can rebuild your RAID by itself. Also, an OS problem won't crash his RAID.

[jhogarty]

I've been considering this option for my video storage (to work with FCP):

miniG

I want external storage because I do not spend all my time on my box editing. So I like the ability to turn off the extra storage when not in use.

I did consider an internal solution from the same people:

swiftData200

With the miniG I was thinking about just getting the case from them, an 8 port external SATA card, and 4 drives at this time. This way I could add another miniG, or similar, at a later date. Plus the miniG looks cool and matches my G5.

Would setup the video drive as Raid-0 inside OSX.

J.

[majesticmac]

http://www.barefeats.com/hard58.html

FirmTek's SerTek/2eEN4 'Direct-To-Backplane'
Four Bay Serial ATA Hot-Swap Enclosure

It matches the aluminum powermacs and it SATA2 but it is $500

I still might get one of these.

[majesticmac]

as a follow up to my original post, I have decided against putting any xtra hard drives in the G5 box. I do not want to put my expensive ram at risk with any kind of heat build up or large power draws that could undermine the components slowly. I considered pulling the optical and putting it in it's own enclosure and utilize the space for the 4 hard drives but I decided it was not worth the cost savings.

I will either get the Burly or the FirmTek depending on if I will buy 4 500g or 8 300g. I was planning on getting the Sonnet 8 external sata2 controller BUT I just read this vague observation from barefeets.

http://www.barefeats.com/quick.html
" October 17th, 2005 -- Lately we've been learning about some subtle differences between true SATA II (3Gbit/s) and SATA I (1.5Gbit/s) hard drives. We were testing 8 Hitachi 7K500 in a RAID 0 set using the SATA II host adapter from Sonnet Technologies. For large 1GB sustained transfers, there is no difference. But when we ran a benchmark using of test files of 16MB or smaller, the drives setup in 3Gbit/s mode were 15 to 20% faster than the drives in 1.5Gbit/s mode. (We realize that the total collective cache of our 8 drive RAID 0 set is 64MB, that that doesn't explain everything.)

We also learned that two 4 port PCI-X host adapters are do small block transfers 20 to 20% faster than one single 8 port PCI-X host adapter."

So back to the drawing board, I will not pony up the extra cost on that card until it is determined to be faster than 2 4 port cards.
QUESTION
Could I set up a 8 disk sata raid with 2 4 port cards and still use the raid software that comes with the G5. I do not want to have to use Softraid programs.

[majesticmac]

Originally Posted by mduell

You can fit a few more drives inside the G5 case with third party addons; 2 or 3 more in addition to the original 2.

External SATA arrays are easy. Get a PCI-X card that has 4-8 external ports (SATA or e.SATA), and then get some external enclosures. You can get enclosures that accept 4 drives and have just one cable back to the computer, but that limits speed greatly. I think you're better off with single or dual drive enclosures with a cable for each drive.

I like your solution of single or dual drive enclosures with a cable for each. I guess the only drawback would be power. Can you point me in a direction so I research single or dual drive enclosures ganged together in a 4 to 8 drive raid. I wonder about power, do the enclosures have indiviual power plugs or do you have to set up your own AC solution.

[OreoCookie]

Originally Posted by majesticmac

So back to the drawing board, I will not pony up the extra cost on that card until it is determined to be faster than 2 4 port cards.
QUESTION
Could I set up a 8 disk sata raid with 2 4 port cards and still use the raid software that comes with the G5. I do not want to have to use Softraid programs.

Your post is a bit ambiguous: OS X software RAID is a Softraid (to use your words). If you don't want to use no software RAID, you cannot use the solution you propose, but you have to use a more expensive RAID tower with integrated hardware RAID. Just take a look at the other thread you also posted in for a few models.

They cost more, are more reliable and might be a bit slower since all drives share one connection. However, if you say, you don't care about security and you want to use a RAID0 anyway, you might as well use a software RAID.

But remember, 8 drives are already quite a few and the probability that your RAID fails is quite large. Maybe you should think of using RAID level 3 or 5 … which means one drive can fail without having your whole RAID go down the drain. Then, a hardware RAID would make more sense, though, as you can change drives on-the-fly and you get better feedback in case of problems.

[jhogarty]

I don't know the technical reasons, but when I setup my Newtek Video Toaster box (on Windows) the folks at Newtek strongly suggested using software RAID in windows and at RAID 0. Even though I have an Escalade IDE RAID controller I used sofware (Windows) RAID 0.

I think the original poster also said he was doing uncompressed video. He pretty much will need to use RAID 0. Yes, if you loose a drive you are screwed. But to get the kind of speed you need, he will need to use RAID 0.

I'd look at two 4 port SATA cards. But, keep in mind you are running out of expansion slots. Do you have plans to add a capture card?

J.

[mduell]

Originally Posted by majesticmac

Could I set up a 8 disk sata raid with 2 4 port cards and still use the raid software that comes with the G5. I do not want to have to use Softraid programs.

I can't comment on the relative performance of 4 vs 8 port adapters, but using OSX built-in software RAID you can build an array from external disks.

Originally Posted by majesticmac

I like your solution of single or dual drive enclosures with a cable for each. I guess the only drawback would be power. Can you point me in a direction so I research single or dual drive enclosures ganged together in a 4 to 8 drive raid. I wonder about power, do the enclosures have indiviual power plugs or do you have to set up your own AC solution.

I can't help you with the SATA adapter, but here is the SATA enclosure I use and like, and here are some multi-drive options.

Originally Posted by jhogarty

I don't know the technical reasons, but when I setup my Newtek Video Toaster box (on Windows) the folks at Newtek strongly suggested using software RAID in windows and at RAID 0. Even though I have an Escalade IDE RAID controller I used sofware (Windows) RAID 0.

I think the original poster also said he was doing uncompressed video. He pretty much will need to use RAID 0. Yes, if you loose a drive you are screwed. But to get the kind of speed you need, he will need to use RAID 0.

I'm very surprised they suggested that, given that you have a hardware RAID card.

For the OP (majesticmac): RAID5 is good for size and availability, but it's not so good for performance (typically has the performance of a single drive). Since I think you want speed (for uncompressed video) and are going to have lots of disks, I'd look toward RAID0+1 for availability and performance, although you do take a size hit (you get [or lose] half of the available disk space).

[OreoCookie]

Originally Posted by mduell

I'm very surprised they suggested that, given that you have a hardware RAID card.

If he were to use a non-trivial RAID level (which means usually level 5), my guesstimate would be that the tech support knew that a software RAID will offer better performance. Although in this case, I'm puzzled, too, since RAID0 is not very computationally expensive and can be handled by the small cpus soldered on ATA RAID cards.

Originally Posted by mduell

For the OP (majesticmac): RAID5 is good for size and availability, but it's not so good for performance (typically has the performance of a single drive). Since I think you want speed (for uncompressed video) and are going to have lots of disks, I'd look toward RAID0+1 for availability and performance, although you do take a size hit (you get [or lose] half of the available disk space).

A RAID0 with 8 drives is risky business. How about a RAID50 (two striped RAID5s) or something like that? He'd have more capacity (effectively that of 6 drives if he uses 8) this way. This way, he can have one drive failure per RAID5, if he uses two 4-bay enclosures with hardware RAID, he'd have hot-plugging capability as well as enough bandwidth.

[mduell]

Originally Posted by OreoCookie

A RAID0 with 8 drives is risky business. How about a RAID50 (two striped RAID5s) or something like that? He'd have more capacity (effectively that of 6 drives if he uses 8) this way. This way, he can have one drive failure per RAID5, if he uses two 4-bay enclosures with hardware RAID, he'd have hot-plugging capability as well as enough bandwidth.

That is another option; here's a list of the four most obvious options:
RAID0 of 8 drives: Best performance (about 8 times the throughput of a single drive), 100% storage space, but lose one drive and all your data is gone.
RAID0 of 4 RAID1 of 2 drives or RAID1 of RAID0 of 4 drives: Next best performance (about 4 times the throughput of a single drive), 50% storage space, and you can be running after losing up to four drives but can be hosed after losing as few as two.
RAID5 of RAID0 of 2 drives or RAID0 of RAID5 of 4 drives: Next best performance (about 2 times the throughput of a single drive), 75% storage, you can be running after losing as many as four drives and can recover after losing as many as five drives but can be hosed after losing as few as three drives.
RAID5 of 8 drives: Worst performance (equivalent to a single drive, possibly lower depending on implementation), 88% storage, you can recover after losing a drive but you're hosed after losing two.

I would go with option two (RAID0+1) for performance or option three (RAID5+0) for storage. The other two are possible if performance and/or storage is key, but ill advised in terms of reliability or performance.

[OreoCookie]

Actually his RAID50 can be hosed after losing two drives (on the same array), three at most.

I'd agree that a RAID10/0+1 (depending on how you shuffle the drives) or a RAID0+5/50 is the best option. I'd lean towards RAID50 or so, as I think the throughput should be `good enough'. With a RAID50, you can get two `smart' 4-bay enclosures complete with hot-plugging, etc. Should also be easier to set up (since the OP doesn't seem to be well-versed in RAID technology).

[jhogarty]

I was surprsied as well when they suggested using software RAID built in to Windows. However, I ran their diag program with both the Windows RAID and the 3Ware hardware RAID, the drives had higher throughput with software RAID.

On a side note, I lost more drives on my video array (RAID 0) then an any of my single drive systems. Prior to my Macs I had 3 desktops, 1 laptop and 1 server. I lost drives in the video array 3 times and 1 drive in my server (was able to recover most of the data). But when I went to install new drives in my video array I ended up replacing the whole array twice. Had to match the drive speed/size/etc.

J.

[OreoCookie]

What's your budget anyway?

[mduell]

Originally Posted by OreoCookie

If he were to use a non-trivial RAID level (which means usually level 5), my guesstimate would be that the tech support knew that a software RAID will offer better performance. Although in this case, I'm puzzled, too, since RAID0 is not very computationally expensive and can be handled by the small cpus soldered on ATA RAID cards.

Software RAID depends on the CPU to do the XOR math, while hardware RAID (where your card actually has a processor like the Intel IOP33x, not a card that relies on the driver to use the CPU for the math) can do all the math itsself and should offer better performance.

Originally Posted by OreoCookie

Actually his RAID50 can be hosed after losing two drives (on the same array), three at most.

Correct.

[fritzair]

I have used a 0 RAID setup for a couple of years in a G4, and have added one to a G5 recently.
I would hook to RAID 0 inside the box, and back up with USB or firewire daily. If you can afford a card, I would buy a SATA card and disk kit, install one more large drive to the G5 SATA controller and switch the RAID 0 to the card. Use the large main drive as a system /apps disk and the RAID for the video load. I found with X bench, only a 50% improvement in throughput with the RAID 0 (Large block cache, 16 MB buffer, 300Gig) with the Mac SATA controller. Haven't been there recently but if you haven't visited "xlr8 your mac", you should.

Mike

[OreoCookie]

Having RAID0 comprised of two drives and having an 8-drive RAID0 are two entirely different things.

You cannot back up data to an external hd with that kind of storage, you would need yet another RAID.

[mduell]

Originally Posted by OreoCookie

You cannot back up data to an external hd with that kind of storage, you would need yet another RAID.

Or some tapes. Lots of tapes.