Can you daisy chain QDR Infiniband?

[Maverick2002]

Not sure how many of you have used Quad Data Rate Infiniband, but we're debating a couple scenarios at work as we put together our own mini HPC farm.

We'll be getting more than 1 QDR quad xeon (2x2 with QDR bridge) system. Connecting the two boards (all in a 1U box) is ~$100 for a single QDR cable, but if we want to connect 2 boxes (4 boards) we then have to purchase at least 2x 1port QDR cards which are expensive ... but still way less than the thousands for a QDR switch.

So, here's my question:

Can you daisy-chain QDR Inifiniband? That is, can you plug anything into anything else and still have them talk to each other (like you can with ethernet)? Or does there have to be some sort of hierarchical system?

Several cards would still be cheaper than a switch if we could make it work.

TIA

 

[Maverick2002]

bump .... should I post this in HT?

 

[Knavish]

Maybe there aren't so many HPC cluster types around here. I haven't looked at it since about 8 yrs ago back in school when I new some guys in a lab building a cluster. They were less than thrilled with their infiniband performances vs. gig-E, but that was probably 1st generation hardware.

There are some other HPC-specific sites out there. You should probably try posting on one of those.

 

[Maverick2002]

I figured someone here would know ... I'm sure there are people working in companies that make use of high bandwidth interconnects. SDR Inifiniband is probably what you're referring to. DDR Inifiniband is the mainstream right now, with QDR being the newer, harder to find, higher bandwidth, more expensive standard. The QDR boxes we're thinking of getting are rated for 40Gbps internally.

If a mod deems this worth to be highly technical, please move it