It should also be noted that the addresses assigned to the iDRAC interface will follow the blades regardless of which slot they're in, so be careful if you shuffle blades around. We did the shuffle to even out the heat load and had to refer to notes to figure out which blade was which. As for the blade NICs, Dell engineering tells me that you can assign up to six NICs per blade through the CMC, and those can appear on either the pass-through ports or on the managed switch. Here's how they broke it out for me:
The nics go in pairs. Think of them as two integrated NICs (Fabric A) and two dual port PCI cards (Fabrics B & C).
In this case, the PCI cards are really mezzanine cards.
Each pair of NICs is associated with a fabric, so 3 pairs = Fabrics A, B & C.
Remember that these choices are on a chassis level.
Fabric A is always integrated NICs, port 1 to switch 1 and port 2 to switch 2. This is for every blade and it gives you redundant connectivity.
Fabric B & C is similar in design, but is Mezzanine card and is labeled B & C which aligns them with the switch modules.
There is no interdependency between the 3 fabrics. The choice for on fabric does not restrict or limit or depend on the choice for any other fabric.
The only mandate is that Fabric A (the integrated NICs) is Ethernet only.
(This is the info on NIC assignment from Dell and currently the NICs are Broadcom flavor only)
Note: Thank you to the Dell engineering support team for the above explanation on NIC assignments.