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SFF8087 "reverse breakout" == "crossover"?

T

TCM

Gawd
Joined
Nov 10, 2011
Messages
641
Hi,

I got an M1015. Until my server parts arrive, I'm testing it in various graphics card slots. It works in an MSI Z68A-GD65 G3 in the second PCIe x16 slot. I flashed it to 9211-8i P11 firmware in that slot, although after erasing the flash I had to switch to sasflash.efi in the UEFI shell, otherwise the dreaded PAL error would occur.

Anyway, I could use the original WebBIOS as well as the IT mode BIOS, so I assume that card is basically good to go.

Then I ordered cables. If anyone cares, they are "SFF8087 to 4x SATA Host to Backplane" cables - supposedly 1:1 or straight-through. From reading various forums I assume those are the right ones. Problem is, the controller sees no hard disk with those cables. I tried an OCZ Vertex 2 as well as some Samsung 500G and a Seagate 1.5T drive.

So from what I've read I know that "reverse breakout" cables would be the wrong ones. However, I couldn't find any statement that connects the two terms "reverse breakout" and either "straight-through" or "crossover".

My strong suspicion is that reverse breakout means crossover and would basically be the wrong kind. But that would mean something is wrong with either my 1:1 cables or my controller. How should I proceed apart from blindly ordering crossover cables?

Edit: I have a basic voltmeter so I could check which pin of the SFF8087 connector goes a specific pin on the first SATA connector. If anyone could give me a hint which pins are supposed to be connected, that would help as well.

Thanks
 
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I am guessing you were supposed to get the forward direction cables not the reverse ones!

On my Norco 4224, if I want to have my motherboard's SATA ports plug into the SFF connector on the drive bays, I would need a *reverse* breakout cable - for motherboard SATA -> Norco backplane. If I want to connect my M1015 to 4 hdds _without_ a backplane, going straight to their SATA connectors, I would need a *forward* connector.

When you order the cables be sure to ONLY order the ones that specify the direction. That is the safest.
 
Somehow forward and reverse are not common specifications here. I can only find 1:1 aka straight-through or crossover.

I just need a definite confirmation that forward equals 1:1 or a specific test I could conduct, e.g. "on forward cables, pin x on miniSAS connects to pin y on the first SATA".
 
Rectal Prolapse said:
I am guessing you were supposed to get the forward direction cables not the reverse ones!

On my Norco 4224, if I want to have my motherboard's SATA ports plug into the SFF connector on the drive bays, I would need a *reverse* breakout cable - for motherboard SATA -> Norco backplane. If I want to connect my M1015 to 4 hdds _without_ a backplane, going straight to their SATA connectors, I would need a *forward* connector.

When you order the cables be sure to ONLY order the ones that specify the direction. That is the safest.
Click to expand...

but some backplanes have sata connectors :)
 
Yeah that's why I mentioned the Norco 4224 - which has SAS backplane only AFAIK, versus the older 4020, which I think has SATA (although maybe they have a newer SAS version haha!)

But yeah, the terminology is confusing - I try to avoid cables that don't have a direction indicator - 1:1 and passthrough and crossover --- what the hell are those? :)
 
When i used the wrong type of cable on my M1015, it would just show no drives connected. Once i got the correct cable everything functioned correctly. So i dont think it will hurt anything to just try the cable. From the description it sounds like the correct cable anyway.
 
How about a link to the cable you bought?
Are you using a backplane or plugging in straight to the drive?
 
4xSATA->SAS = reverse breakout (4->1)
SAS->4xSATA = forward breakout (1->4)

I made the same mistake

to connect 4x SATA on your mobo to a SAS backplane you need reverse breakout, to connect SAS on your HBA to 4x SATA HDD you need a forward breakout

cheap forward breakout: http://www.monoprice.com/products/p...=10254&cs_id=1025406&p_id=8186&seq=1&format=2

edit: SFF8087 to 4x SATA Host to Backplane is a reverse breakout, it goes from 4x SATA (broken-out to 1 SAS), the forward break out goes from 1x SAS and breaks-out to 4x SATA
 
If it's any help: http://translate.google.com/transla...Line,MiniSASSFF8087an4xSATA,11,50cm,bulk.html

Reading the description again, "for connecting controllers with SFF8087 connector" is badly translated. In German it could mean for connecting controllers TO a SFF8087 connector or for connecting controllers WHO HAVE a SFF8087 connector. Also, if the packaging reads "SFF8087 to 4x SATA Host to Backplane" I naturally assume the host is SFF8087 and the backplane gets 4x SATA, which would be correct, right?

I don't get why they don't just use forward/reverse here as well. SIgh.

Could anyone just grab a connection checker please and tell me pin 1 on miniSAS is pin y on SATA port z on a working cable?

Thanks
 
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After a bit of googling it appears that

1:1 = straight through = reverse breakout

Crossover = Forward breakout
 
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