Was this ever figured out?
I'm wanting to get the XL710-qda2 card, toss it into ubuntu nas (truenas scale), using a breakout cable to a Mikrotik CRS317-1G-16S+RM switch, LAG them up and let the NAS have 40gbit.
This possible? Or just go intel dual 10gbit LAG'em up and have 20gbit?