cannot access device on physical LAN interfaces

[javiermi]

HI
I have just installed opnsense  ( last version) on a mini pc and my plan is to replace my checkpoint UTM firewall at home, so I want to set everything as the current firewall, then switch over
I got a separate Internet connection ( for a week - until is disconnected), so wanted to connect get teh software updated and test the connections on the second link, just with one PC
I basically just set a wan, opt1 and lan interfaces , and if I connect the lan or opt interface to my lan ( via a switch), I can access the opnsense box no problem
However, if I connect a computer to the opt1 or lan interfaces directly, I simply cannot even get an ip address ( if using dhcp) on my laptop
I even tried to use a switch to connect to the port, al to no avail
Tried 3 computers - linux and windows and on Linux the link goes up, and then I get a "activation of network failed" message after a few minutes
Currently there are just the basic  - any -any  - firewall rules, so don't believe the firewall is the culprit
I'm a relatively experience network guy, so I am completely confused

It is as if at layer 1 ( physical) , or  2  ( data link) something is failing

Any help wil be appreciated

[Monviech (Cedrik)]

What kind of Network drivers does your mini PC have? I have read a few times that if it's "realtek" you have to install the "os-realtek-re" plugin to have functioning network drivers.

And if it's USB NICs connected to the mini PC things can get weird too.

If you have rather weird hardware, maybe you should put a hypervisor on it to virtualize the hardware.

EDIT: You should definitely post your exact hardware so the people who know a lot about hardware can help you.