sata to sata over sas silliness

honegod

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context : I want a bunch of sata harddrives in a housing outside my computer case, the computer has only sata data sockets.
so, instead of having 12 sata cables running from housing to case, using 3 sas 8088 cables would do the same thing, just much tidier.
this would require using sas breakout cables to concentrate 4 harddrive sata data cables into a single 8088 cable, with a sas breakout cable at the case end to use the 4 motherboard sata sockets.
( times 3 to total 12 drives)

my problem is that sata and sas are electrally different and the common use case is adapting sata to sas or vice versa.
which I do NOT want to do here.

finding out exactly what the difference is turns out to be nontrivial.

so choosing which style breakout cables at each end will let me have sata style data transmission end to end, seems to be a silly quest, since apparently this use case is inconceivable.
 
You need forward breakout cables on one side (SFF-8087), reverse breakout cables on the other side (SFF-8087), 2 4x SATA internal to SFF-8088 External slot adapters and a SFF-8088 cable. Should do what you want (theoretically) as long as you keep it really, really short (less than 3 feet all in on all cables (meaning none of the 3 cables can be longer than 12") and even then with essentially 6 hops could create resistance problems, reflection issues or signaling issues. (SATA-8087-8088-External8088-8087-SATA)
 
2 4x SATA internal to SFF-8088 External slot adapters
implies that a FEMALE 8088 socket to 4 sata plugs, which would eliminate the need for these adapters is another inconceivably silly notion ?
 
like this

External-Mini-SAS-SFF-8088-Female-to-4-SATA-Reverse-Cable-3-768x768.jpg
 
Yes. Just keep in mind, as I mentioned since you are staying in a SATA domain overall link length is a significant limiting issue, and the longer you go the worse it gets. The particular model you listed would make it much too long overall with one on each end, plus the 8088.
 
overall link length is a significant limiting issue
yes.

the example I posted was the ONLY specimen I was able to find of this exact plug configuration.
wire cutters and a soldering iron can fix that particular problem.
 
You could opt for a SAS HBA in IT Mode with external SAS port and a SAS expander in the case with the drives.

no.
good setup, but.
the HBA and SAS expander business is out of the question here.
hardwired sata to sata is the specific goal.
the current plan is 12 sata cables in a huge wad from computer case to drive housing.
the 8088 business is purely to cut the cable clutter from 12 + power to 3 + power, with the added benefit of simplifying disconnecting the drive enclosure from the computer case for simplifying service.
 
yes.

the example I posted was the ONLY specimen I was able to find of this exact plug configuration.
wire cutters and a soldering iron can fix that particular problem.
Yeah, not as much as you might think. These are extremely thin, stranded leads that do not take kindly to being modified (.125mm difference in the overall length of just 1 of the leads in a particular connector can be enough to throw off timings).
 
no.
good setup, but.
the HBA and SAS expander business is out of the question here.
hardwired sata to sata is the specific goal.
the current plan is 12 sata cables in a huge wad from computer case to drive housing.
the 8088 business is purely to cut the cable clutter from 12 + power to 3 + power, with the added benefit of simplifying disconnecting the drive enclosure from the computer case for simplifying service.
I get what you are trying to do. Unfortunately, it is not really practical if you want reliable data transfer. Either build a cheapo enclosure with a power supply and SAS expander(as mentioned by Zepher above) and make a DAS, or build a box and make a NAS (and/or also add a few Mellanox 2's and a passive cable and get yourself 10Gbit equivalent speeds between the two boxes (via the ConnectX connection) and gigabit to the rest of your network via Ethernet!
 
a tolerance of less than +/- 2.5 thousanths of a freedom unit in wire length is, admittedly, slightly daunting.
a sata plug soldering alignment jig sounds like just the thing, since each sata plug needs a different length wire to get to its individual sata socket.
 
not really practical if you want reliable data transfer
is this true using the 12 unmodded sata cables to a box sitting beside the computer ?
24" sata would be more than enough for this.

or is it close enough to the boundary that the added complexity of all the inline plugs would tend to push it across the border.
 
is this true using the 12 unmodded sata cables to a box sitting beside the computer ?
24" sata would be more than enough for this.

or is it close enough to the boundary that the added complexity of all the inline plugs would tend to push it across the border.
Just snaking SATA (up to 36") and power (a reasonable length (don't wire wrap them together)) could accomplish what you are looking on a point to point connection, but may be a problem if you bundle them as even with locking SATA connectors the tension from the inner and outer cables (or a bundle) may tug on each other and possibly detach once or more over time.
 
I went the simple route with my setup, 12 drives in this machine with a 2.5GbE nic.
IMG_2222.JPEG IMG_1195.JPEG
 
may be a problem
yes.

car audio taught me about not running power and signal cables together.
also about the importance of strain relief.

the sas cable business is looking more silly as a homebuilt solution the deeper I look.

I do not particularly want to build a precision sata plug soldering fixture, so I can solder 24 sata plugs.
 
a second computer just to run the drives seems excessive, to me.
fun, but figuring out how to do it my way seems more fun, to me.
It's also my Plex server and file server.
If I just wanted an external drive, I would do the SAS expander in there in place of the motherboard, and a PCIe riser to power the Expander.

I'd like to see the setup you come up with, post some pics when you have it built.
 
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