probly not relevant to you but thought i might chime in’since you mentioned X520
i’m using this
1 x 10Gtek 10Gb PCI-E NIC Network Card, Single SFP+ Port, with Intel 82599EN Controller, PCI Express Ethernet LAN Adapter (seller said this is similar to either the “X520-10G-1S-X8 or X520-DA1” for compatibility)
For my project over here
i listed the optical transceivers i use and other assortment of hardware for my setup.
But basically i got this SFP+ pcie and the fiber optic transceivers to work for my desktop to switch, and also from nas to switch.
in the beginning it didn’t work for the NAS back when i was using QTS on the QNAP. But after i changed it to Truenas it worked.
So maybe you are in a similar predicament in that sense? my case i had to switch to a different os which apparently supported it but the previous didn’t. Thought you’d be interested to know.
fyi i’m using a different brand switch than yours.