Trouble with 2 x C240 M5s connecting back-to-back via VIC 1387s

[GarrettSkj]

As the title suggests, I have 2 x C240 M5s which I'm attempting to cable back-to-back using the VIC 1387 interfaces, I have attempted to use Passive DACs (TwinAX), Active Optical DACS (AOC) and some BiDi optics, all QSFP/QSFP.

(Firmware is 4.1.3, and MLOM firmware is 4.4.3a)

The VIC interface LEDs do not light up when cross connected (which I would expect for Layer1)

CIMC reports the Link State to be "Link down" in both cases.

What am I missing? My use case is a two-node VMware robo-cluster. I'm able to use some Mellanox NICs and it works fine, but I'd prefer to use the VIC interfaces if possible.

[Kirk J]

My first guess, is that these are CNAs, with a whole list of 802.xxx capabilities that normally require a nic/switch interaction to negotiate.

I don't think you are going to get those to correctly link.

I'm pretty sure you can use the 2 Intel based 10/1 Gb LOM ports that are RJ-45 based , but not the VIC cards on a back to back type connection.

Kirk...