We're encountering a strange problem, which involves 3* servers with the same HW as in the title (Lenovo Thinkserver RD650MLK with 4* Intel x520-DA2 adapters - 3* PCIe, 1* on board - total of 8* 10GbE SFP+ based ports).
After installing vSphere 6.x on all the servers, we're encountering the same problem on all of them; all of the NIC's are viewable within the vCenter, BUT only the 1*on-board x520 is actually working. The rest of the PCI-e cards are not working at all (with or without transceiver connected light).
Elimination which we've tried:
Using same transceivers (from the External x520) on the internal - all are working well.
We're about to install the a new OS (MS Win server based) - so we'll be able to eliminate it on the OS level as well
We would appreciate your advice, since it's a new production environment which is critical to our customer.