I am a total newbie to Opnsense and configuration of a router. Need help with the configuration - WAN interface.
Even though the WAN interface NIC in the mini pc network cable is connected to the ISP fibre optic modem, the PC doesn't recognise that. The interface doesn't get any public ip from the ISP. Its not the cable fault, because the same cable and connection to Internet works properly when connected to an Asus router. The domain name resolution fails, may be because correct public ip and dns server names not retrieved.
Please refer to the pics attached.
Even the option to update the package in the terminal mode is not working... Is there any configuration missing? Please help.
You get a WAN IP in the 192.168.1.0/24 range (WAN IP 192.168.1.5 in the screenshots) and your LAN IP range is also 192.168.1.0/24. These two IP range must not be the same, if you change the LAN IP range to something else, e.g. 192.168.10.0/24 there is a good chance you get onto the internet.
But it will still be no public IP, that is true. Did you get the ASUS router from your ISP? And did you get any instructions from your ISP how to use your own router? And does the ASUS router get a public IP?
First things first. Does you modem support bridge mode? If not, you are in for a lot of pain and double NAT.
What ISP do you have?
Since you have fiber, you are probably better off by just getting SFP+ for OPNsense. That way you can ditch the ISP router.
If for some reason (like phone or TV) you really need to use your ISP router, maybe it has a DMZ option you can put your OPNsense behind.