Newbie SAS cabling question

[DanTheDataMan]

Hello all,

I'm in the process of building a ZFS NAS and decided to push the boat out and use SAS instead of SATA drives. After doing some research I settled on the Lenovo M1215 flashed to IT firmware, connected to a set of HGST HE10s. Unfortunately I ordered two SFF-8643 to SATA breakout cables to connect everything together but discovered last night that what I actually need on the drive end is SFF-8482.

I'm having some trouble finding decent cables and wondered what everyone else does? There are some on ebay that look suspiciously cheap but otherwise they are quite difficult to find and it makes me think I'm missing yet another thing somewhere. My main concern is that I've gone to town on the rest of the hardware and don't want to spoil the whole thing for the interconnects. Also, of the few cables I've found, some are only rated for SAS 2 (6 Gb/s), and most have molex power connectors (which also seems odd given the SATA power has been available for about a decade). I can of course use adapters if necessary.

Very grateful for any help!

Thanks,

Dan

 

[DanTheDataMan]

I should add that I'm based in the UK so if anyone has any supplier suggestions, I would prefer local although of course I will import if necessary!

 

[maxf]

You'll probably want one of these:

• LSI L5-00222-00
  They seem to be on backorder everywhere, I have yet to find someone who has them in stock.
• Delock 83390
  Apparently there are multiple revisions, also some shops mix this up and call it a 'miniSAS' adapter, so I'm not too sure about this one.
• Adaptec 2280100-R
  There is also a version with right-angle connectors(2279600-R), but that's probably not what you want on an M1215. They are surprisingly cheap (~20 Euro), I ordered one. Should arrive next week...

 

[DanTheDataMan]

Thanks for taking the time to reply maxf, much appreciated! Those cables look like the right connectors but they all(?) claim to be rated only to 6Gb/s SAS - do you think they'll work up to 12Gb/s? Maybe it doesn't matter? I don't expect that any one drive will push the lower limit but I still feel a bit like I'd be selling the rest of the hardware short; on the other hand there don't seem to be any 12Gb/s rated cables like this and I don't understand why :-/ I feel like I'm missing something important!

Anyway thanks again - if you or anyone else here have any other thoughts I'd love to hear them.

 

[DanTheDataMan]

So I randomly dicovered serialcables.com and emailed them for advice - it turns out my mistake is that I don't in fact want an SFF-8432 connector break out cable - those are for 6Gb/s drives only and that's why I couldn't find any 12Gb/s rated cables; the 12Gb/s drives use an SFF-8680 connector instead! So now it all makes much sense - hope this is useful in future to anyone else who find themselves as confused as I was :-D

 

[DanTheDataMan]

Update - upon further investigation I came to understand that SFF-8482 (not 8432) and SFF-8680 refer to pin-identical connectors but the latter is rated for SAS 3 (i.e 12Gb/s); of course this makes sense even if only from the point of view of backward compatibility. Secondly, although the cables @maxf mentioned are only SAS 2 rated, since the drives are not capable of pushing data at even that speed, having a down-rated cable should cause no trouble as the controller and drives can negotiate a slower speed on the wire if necessary without impacting overall data rate. Anyone interested in delving into the details of the specs can find the relevant documentation here: http://www.snia.org/sff/specifications

So, thanks again - I've ordered the Delock cable and hopefully that will do the business.