Really stumped. SAS or SATA

brobins

brobins

brobins

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Hi there,

I work in CGI Advertising and run a half decent dual Xeon rig (2x Xeon 3.33Ghz 6 Core, 48 GB ECC Ram, 1x 120GB SSD, 1x 1TB SATA, Quadro 4000 GFX, etc) for 3D Rendering work. Its a good few years old but still very capable for my needs so I am not looking to replace it just yet.

What I do need however is more internal storage. I have been toying with the idea of adding 4x SATA drives in a Raid 0 or 10 array but after looking inside my machine I realised that I only have 2x spare SATA controllers remaining. I also noticed that I have 2x unused SAS controllers on the board.

My question is based around how best to connect up the additional HDD's to the board? The board is a Supermicro X8DA3

Could I connect all 4x of the SATA drives to one SAS controller and run them in a RAID?

Or would i be better to opt for 2x SAS drives and run them in RAID?

Or would it be better to hook my optical drives up the the SAS controllers freeing up the SATA controllers for the additional HDD's?

I just need to add more storage to my rig, at least 2GB, and I would like it to be quick for working with large files.

Really appreciate any advice.

Thanks,

Ben
 
With those 2 SAS ports you could connect up to 8 SATA drives with a pair of breakout cables.

Added a picture to show what I mean. This is my old AMD Opteron board. It had two SAS ports. The cable in the picture is an SFF-8087 to 4xSATA.

UHhwm9d.jpg
 
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Ahh, thanks for the tip. I guess there isn't any throughput restrictions by connecting 4x drives per port? Seems like the solution I need.

So would you advise to stick with SATA HDD's rather than SAS HDD's?

Thanks again.
 
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Sorry for late reply, I went out after I posted the above.

Your board uses the LSI SAS1068E controller for SAS. It's a 3 Gb/s chipset and you might run into some problems with drives over a certain size. The maximum it can see is 2TB (as far as I know, I'm not sure if there's a firmware update that resolves that issue). 6 Gb/s drives will work as they're backwards compatible with 3 Gb/s, but they'll only be able to run at 3 Gb/s speeds because of the limitations of the onboard SAS chipset and you'll still be limited by size (again, in so far as I understand it SATA / SAS backwards compatibility).

The other alternative if your SAS chipset has the above limitations and you want to use drives larger than 2TB and with 6 Gb/s speeds is to use a more modern PCIe card which supports larger and faster drives. For example, in my own server I use an LSI SAS 9201-16i HBA card. It's a 4 port HBA card and I have 12 SATA drives connected to it via 3 SFF-8087 cables. There's the LSI SAS 9207-8i which is the 8 port version of the card I use. There's also the AOC-SAS2LP-MV8 which is very cheap, but doesn't do RAID. Only JBOD. Which isn't a problem if you're using something like Linux and using mdadm, btrfs or zfs, but might be if you're using Windows. I'm not sure, it's been a long time since I've used Windows as a server / workstation.

When it comes to actual drives... I use SATA, simply because 1: they're cheap and 2 I don't need the speeds and stuff SAS offers.
 
Thanks for your reply. The plot thickens!

After taking all into consideration I am now leaning towards just ordering 2x large SATA drives and connecting them to the free SATA ports on the mobo and running them in RAID 0.

At the end of the day, this rig will be 5 years old next July and although its still more than capable for my needs now I feel that it will be time for a new one at some point in the next few years anyway, so I am a little reluctant to spend too much on it. The card you mentioned would be a good idea but it costs roughly the same as what I paid for this motherboard :o

Thank again for the advice.
 
Hi there,

I took the plunge and ordered 4x 2TB SATA drives and one of the cables you mentioned. I am however having issues as the drives are not being recognized at all, in fact, the SAS controller doesn't even show up in the BIOS nor in Windows.

I was wondering if you might be able to offer some advice on how to get them to show up, etc?

Thanks,
 
I'm too late to the party, but is this a SOHO system or are you in an office with an IT support crew? Because if it's the latter and the issue is longer-term storage, I'd get a faster LAN connection and leave the details up to them. If you want fast, local, temporary storage, get yourself some 1+ TB SSDs.
 
Panic over. It turns out SAS was disabled on the motherboard via a jumper, weird as it should be enabled by default but all working now.

Quartz - Yeah this is a SOHO system. Im happy with the 4x 2TB HDD's for now. Future plans include building a dedicated file server, a 10gb network and a new dual 18 core workstation. But for now, this solution will keep me going.

Thanks for all the advice people!

Ben
 
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