SAS controllers

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Benoire

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# 138258 27-Dec-2013 10:48

Hi,

Not sure where to post this so thought this might be more appropriate.

I have a home ESXi server which I use for active directory, exchange and as my media/live tv server. I'm about to run out of SATA connectors and need to add more. I've found some cheaper, older LSI megaraid SAS controllers capable of Sata II with up to 8 devices attached. I ideally would like to future proof to Sata III but really do I need the 6GBps when I will be using it for mechanical drives not in raid mode? Is there any need in getting a more modern SAS controller for the initial expansion if I'm simply doing JBOD at a mechanical level?

Any suggestions on types of SAS cards would be gratefully received!

Chris

insane

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# 957897 27-Dec-2013 10:58

I suspect you'll be paying a premium for something you'll hardly be using, how many times will you be bursting past 3gbps given the kind of spindles you have and the workload they will be supporting?

Zeon

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# 957912 27-Dec-2013 11:30

It doesn't matter if you are on even SATA1 or SATA0.5 if it existed - you need a RAID card with write back cache. Without it you may get a sustained write of 5MBps (if you have a lot of VMs this will reduce considerably) even on a SATA9000+ 7200RPM HDD. There may be some cheap ones on Trademe.

There is an old Adaptec 5405 with 256MB write back (and a BBU - not sure of the BBU's condition but new batteries aren't hugely expensive. You may want to do some research on the need of a BBU when you have write back) at work.

PANiCnz

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# 957943 27-Dec-2013 12:57

The problem with the older LSI chipsets (ala LSI 1068e) is that they don't support drives bigger than 2TB which is more likely to be handicap than the speed limitations. At a minimum look for something with the LSI SAS 2008 chipset, the IBM M1015's can be bought for about $130 NZD off TradeMe if you're lucky or eBay worst case.

If you're not using the card's RAID functionality then you do not need write back cache or BBU. If you're not using the RAID functionality you can even cross flash the firmware so the drives are exposed to the OS without any fluff enforced by the controller.

JamesL

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# 957945 27-Dec-2013 13:06

I've got two of these http://www.amazon.com/dp/B002RL8I7M/ref=pe_385040_30332190_TE_M3T1_ST1_dp_1 to replace the older LSI1068e chipset sas card I had

Works well, flashed with the IT firmware and using ZFS

Benoire

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# 958024 27-Dec-2013 17:30

So really as I am only wanting to pass through the HDDs (with SMART info) for JBOD I don't really need to consider the raid functionality of the card? On another forum it has been suggested that one of these HP cards might do what I need: http://www.ebay.com/itm/Short-Bracket-HP-Smart-Array-P400-SAS-RAID-CARD-447029-001-256mb-mem-no-battery-/221195640815?pt=US_Server_Disk_Controllers_RAID_Cards&hash=item3380499fef

They do SAS with 8 ports at 3Gbps for Sata II and can expand up to 18 devices although it only supports max 2tb drives... I'm looking at something to start me off as I slowly build my media storage.

PANiCnz

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# 958032 27-Dec-2013 17:43

Not idea why someone is recommending a P400, they are an old card. If you're going to shell out some cash surely you want a card that supports 2tb+ drives?

The M1015 is just a rebranded LSI9211-8i with custom IBM firmware. A number of manufacturers rebrand the same card, even Intel sells the a LSI9211-8i as a RS2WC080.

To get the best results with an LSI card you will want to cross flash it.

If all this is too daunting perhaps look into a Highpoint card or something similar.

Benoire

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# 958055 27-Dec-2013 18:19

Nope none of this is daunting to me, I just want the ability to add more connections to my ESXi 5.5 server for JBOD use as I do not need raid.

What does a modern controller bring to the table compared to the P400 for my needs (a genuine question as I am trying to figure all this out)? Higher bandwidth (is this really useful given mechanical drives do not have the throughput currently to make use of the bandwidth), support for larger disks (important but as I tend to Trade Me my HDDs I'm happy to expand with smaller drives as it will take a while for me to need 3TB drives), better raid functions (not going to raid anything)?

What else? As an example, the P400 can be got for around $30NZD delivered and that gives 8 ports at SATA II Speeds, SMART transfer to host etc... Is there a need for the LSI 9211-8i etc. for my use?

Zeon

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# 958107 27-Dec-2013 21:50

How many drives do you have? Use a SAS expander?

Benoire

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# 958110 27-Dec-2013 22:04

Currently have 6 drives of various sizes connected pooled together in Server 2012 R2. Don't you need a SAS controller before you can actually use the expanders? I've got a consumer grade mobo using IOMMU for VM passthrough so I would need a controller card first?