1

I would like to connect six HGST He10 SAS drives (model 0F27402) to a Lenovo M1215 HBA using direct cabling. I originally bought two SFF-8643 to 4*SATA breakout cables before seeing the drives as I naively thought the connector compatibility between SAS and SATA went in both directions (not so). After hours of research, I have reached the conclusion that I need SFF-8643 to 4*SFF-8680 cables (since everything is SAS 3.0) but I have read a handful of posts by people using the same HBA and SAS 3.0 drives with SFF-8643 to 4*SFF-8482 cables.

This has confused me considerably because the only SFF-8482 cables I can find say they are rated for SAS 2.0 (6Gb/s), although they do appear to be pin-compatible with the SFF-8680. In either case, suppliers of any of these cables appear to be very thin on the ground (particularly in the UK, where I am based) which makes me think I'm missing something important (or multiple things).

My question then is: how should I cable these drives to this HBA?

As a bonus, can anyone recommend learning resources that cover SAS 3.0 to help me answer questions like: what is the difference between SFF-8482 and SFF-8680? I have searched and searched but clear, up-to-date information seems maddeningly elusive.

Thanks in advance!

  • 1
    Do you perhaps mean SFF-8482 instead of SFF-8432? SFF-8482 is the same connector for SAS2 as SFF-8680 is for SAS3. That said, it may not work (reliably) with SFF-8482 or not at full speed (which won't matter with HDDs). – Zac67 Aug 25 '17 at 21:07
  • @Zac67 Thank you, yes! Edited accordingly – Dan Parsonson Aug 26 '17 at 22:01
  • Use a server or a JBOD enclosure to hold the drives? Use something with an expander backplane to hold the drives? What are you doing? – ewwhite Aug 26 '17 at 22:52
  • @ewwhite Alas all drives are going to be in a desktop PC case with no backplane of any kind present - hence the requirement for direct cabling between the HBA and the drives. With hindsight SAS wasn't the right choice for this project in some ways, although on the other hand I have learned a lot... – Dan Parsonson Aug 29 '17 at 17:30
2

From my comment: SFF-8482 and SFF-8680 are essentially the same connector (fitting to a drive's back), the former SAS2-compliant, the latter also SAS3-compliant. With HDDs, this won't matter in practice as they won't go faster than SAS1 speed anyway.

You can find all details to SFF standards on snia.org.

  • Thank you - on further reflection that makes sense also from the point of view of backward compatibility. Thanks also for the SNIA link, very useful! – Dan Parsonson Aug 29 '17 at 17:27

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.