Boot off RAID 0 in Mac Pro

[Data]

Yeah getting some SSD's in there is probably the fastest i can get my system,thinking in that direction myself too.

 

[brand]

As far as what the drives can do, no, it's not wrong.

Actually SSDs would be faster than SAS drives for a boot drive.

 

[nanofrog]

Actually SSDs would be faster than SAS drives for a boot drive.

That comment was only in reference to what was on hand, not a general statement.

If you read the various posts, even another in this thread, I state that SSD is faster at random access than mechanical (SATA or SAS). But that may not be the primary need, and sequential access will take precedence, particularly as budgets may be too small. Each users needs aren't necessarily the same, so the solution is customized to fit all the constraints.

 

[Data]

I decided to go with an external raid so i'm selling my Apple Raid card plus the 4 sas drives: 3 drives are : ST3300555SS ( used dont know how old ) , and 1 is : ST3300656SS ( couple months old ) for 900 euros if anybody is interested, i hope i'm not breaking any rules here by saying this in the thread.

 

[cristian.huiu]

eBay.

You can't use the SAS disks on the logic board, so you will need a card for that. Sorry about any confusion here.

Assuming you don't need additional ports (4), then take a serious look at the ARC-1212 (linked above). 4 port, SAS card, and it can boot OS X once it's been flashed with the EFI firmware.

I've used them professionally and for my personal system as well (different models, but the one linked will work quite well, as it's very similar to the 1680 series, just SAS expander support was eliminated).

Assuming you use this card (or another), you can do what you want with it in terms of array level (provided you've enough drives for the levels it supports). As you've 4x SAS disks, you can even go with a RAID 5 if you choose.

Just make sure you've a UPS, and the battery option for the card is a good idea too.

How did you installed ARC 12-12 in MacPro ? Your MacPro si 2009 or 2010 model ?

 

[nanofrog]

How did you installed ARC 12-12 in MacPro ? Your MacPro is 2009 or 2010 model ?

I no longer have a MP (had a 2008, which wasn't the best fit for my storage requirements; possible to do, but too costly, and what little OS X software available wasn't very good vs. Windows based products <equivalents, not the same vendor selling their products cross-platform>).

But the installation in a 2009/10 system isn't that difficult, once you get the HDD's connected.

Now assuming you're using 3.5" drives, and want to use the HDD bays in the MP, you'll need an adapter kit (here). Just make sure you read the descriptions at the bottom of the page in order to select the correct model number for your system, as there are differences that cause the kits to differ slightly (= wrong kit won't work in your system).

Your other option, is to use 2.5" or 3.5" HDD"s in the optical bays (in the case of 2.5" drives, 4x will fit in a single bay with the right adapter). 3.5" drives are more of a challenge, but possible (again, it involves adapters). I'll skip the details ATM, as I don't have the impression you're after this sort of implementation.

Basic Installation:

1. Install the card's drivers.
2. Install any adapters and the cabling that comes with it (Maxupgrades includes both power and data cabling needed).
3. Once you have the drives connected to the correct cable (SFF-8087 * 4i SATA/SAS breakout cable), you install the card, and connect the cable (SFF-8087 end) to the card. SATA/SAS ends go to the drives (you should recognize these).

Please note, that this is just the physical installation.

I'd recommend keeping the boot disk separate from the array, and at least to start, on one of the SATA ports in the MP itself so it can find the OS X installation. The empty optical bay is great for this, and the connector in a 2009/10 system contains both power and data (you'll have to use Disk Utility to point to the proper disk for the boot volume if you move it from its existing port, which is almost certainly going to be necessary, as it's common for users to connect all 4x HDD bays to the RAID card).

The easiest way to do this, is to use one of the new disks (do this immediately after installing the RAID card drivers, but don't do anything else with the card or existing disks in the MP = no additional hardware stuffed in at this point).

1. Install one of the new drives in an HDD bay (the data will be temporary).
2. Clone the existing OS volume to the new disk.
3. Set the new disk as the boot volume.
4. Shut down.
5. Move the original OS disk to the empty optical bay.
6. Restart.
7. Set the original OS disk now in the empty optical bay as the boot volume.
8. Shut down.
9. Proceed with the hardware installation described above.

 

[alphaod]

alphaod: those numbers are really nice, but they seem too high, for a set of 4 VR's.

What's the file size used in the tests?

I ask, as it appears that the data is being skewed by the cache (which is nice, so the numbers are accurate for small files). But if you want to know what it does on a file larger than the cache can contain, you can do a couple of things.

Mmmm… old thread, but seeing it's be resurrected, I figured I'd run some test on my RAID5:

 

[nanofrog]

I say we put it back to bed...