`I haven't checked the Supermicro models lately, but the HP DL380Gen9 has a model with 24 direct-wired 2.5" slots in 3 modular 8-disk bays. The SAS expander is an add-in card which you don't have to buy.<div><br></div><div>It's really excellent for Intel DC <span></span>s3X10's. Of course it's also more expensive than a Supermicro. </div><div><br></div><div>Hopefully Supermicro has something similar now. Wiring anything SATA through a SAS expander is a risky practice.</div><div><br></div><div> -- Trey</div><div><br><br>On Friday, February 19, 2016, Bob Friesenhahn <<a href="mailto:bfriesen@simple.dallas.tx.us">bfriesen@simple.dallas.tx.us</a>> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Fri, 19 Feb 2016, Peter Tribble wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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So that was an interesting question, and I had to go away and investigate further.<br>
So the way this works is that the system has a 24-slot disk backplane. The disks plug<br>
into the backplane; you have to connect the backplane as a unit to something, which<br>
is where the HBA comes in. It doesn't look like there's a way to wire an individual drive<br>
to an onboard SATA port.<br>
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These really dense 2U systems are often a pre-packaged (or close to it) system from SuperMicro and you get what they (SuperMicro) are able to build. The product page usually makes note of that. Your integrator/builder is only able to make relatively small changes. Direct wiring 24 drives in a 2U system would be crazy.<br>
<br>
With SAS driving SATA, it seems like you would still need/want one SAS channel per drive and 24 channels is a lot. It sounds like you are getting only 8 SAS channels.<br>
<br>
Bob<br>
-- <br>
Bob Friesenhahn<br>
<a>bfriesen@simple.dallas.tx.us</a>, <a href="http://www.simplesystems.org/users/bfriesen/" target="_blank">http://www.simplesystems.org/users/bfriesen/</a><br>
GraphicsMagick Maintainer, <a href="http://www.GraphicsMagick.org/" target="_blank">http://www.GraphicsMagick.org/</a><br>
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