I'm getting ready to put together an updated 24 bay JBOD setup.

I was going to build it with a controller similar to my existing rig:

Computer in the same case with internal sata to backplane using something like the

9305-24i

No sweat.

 

But then I came across some external 24 bay drive shelves, which are a little more foreign to me.

The first has two SFF-8644 slots, which makes sense to me. Each controls 12 bay and could be run off a single 12G SAS HBA card

like a Dell T93GD

I worry about a bottleneck during partiy, but it might be an option.

 

The second case has 3 SFF-8088 ports.

What I can't seem to wrap my head around, is there doesn't seem to be anything that can drive 3 8088 ports directly

(ie. some form of 24e card)

I'm guessing there's already some form of port multipler in play on the drive chassis since each channel would drive 8 bays.

What kind of single card would I use to drive 24 drives off 3 channels?

Would I instead be into a 2 card situation (a 16e and an 8e) to drive this or would I run an additional expander off the controller giving me a 3rd port?

 

I only plan to run spinning disks, but with that many discs I'm mindful of the parity check times.

Being able to use a single card opens the possibily that I could use a SFF PC in conjuction to reduce the power somewhat, but I'm not set on that

 

 

 

 

If the backplane includes a SAS expander, and most 24 ports backlplanes will, you just need a single wide link from the HBA to the enclosure, though it will likely be bandwidth limited, max you can have two wide links for dual link, the third port can be for cascading.

Ah that's interesting, and helpful.

Sounds like the internal 24i soltuion might be somewhat better (evening if it's in a sigle 8x slot)