The "Dual 10G Ethernet Controller CNA SFP+" is probably a X1139A or X1140A. You can confirm this by running "sysconfig -ca" on the controllers.
X1140A comes with empty SFP+ cages and is intended to be used with TwinAx cables. X1139A comes with SR optical SFPs. According to the Product Bulletin, it is not allowed to install SR SFPs in the X1140A, or remove the SFPs from the X1139.