I'm new to OPNSense and I'm currently running into an issue. Is there a list of NICs that are confirmed to work without an issue? I purchased a Syba Dual 2.5 Gigabit Ethernet PCI Express PCI-E Network Controller Card and for some reason it's not seeing it. I think I'm gonna be stuck with a card that won't work. :( Any help is appreciated.
OPNsense is based on FreeBSD so support is dictated by the kernel: https://www.freebsd.org/releases/13.2R/hardware/
No guarantees but a better indicator than most
The Syba adapter is base on Realtek RTL8125, so you have to install the os-realtek-re plugin, because FreeBSD does not support that chipset out of the box.
If you don't have any connectivity on your OPNsense you can manually install the Realtek vendor drivers with the os-realtek-re.pkg plugin from https://pkg.opnsense.org/FreeBSD:13:amd64/23.7/latest/Latest/
pkg install os-realtek-re
Here is also a tutorial but with the driver directly from Realtek.
https://cyberdean.fr/blog/realtek-driver-free-bsd/