September 2023 Bits

September 29 - Debugging OPNsense on MyResNet

I fucked up OPNsense so I couldn’t join the LAN. So I now had to get Proxmox on some sort of a LAN. First, I stopped the OPNsense VM. I change /etc/network/interfaces to get it to use DHCP to connect to MyResNet, hoping their private network feature would work like a LAN. It did not. With my laptop and server connected to MyResNet, they got IPs of 11.21.38.66/26 and 11.97.161.90/26 respectively. So, I cannot even ping my server while on MyResNet. “Personal Area Network” my ass. Maybe it just doesn’t work because one of my devices is on Ethernet and the other is on WiFi? Eh. Whatever.

So new plan is going to be to use the extra port on my dual NIC to plug my computer directly into. Since OPNsense isn’t using it for anything anyway, I should be able to plug my Ethernet cables back the way I had them and not worry about OPNsense getting in the way of anything when I boot it back up. This of course requires me to play around with /etc/network/interfaces again. Wait, new plan, I have a simple travel router. This means I can do the same thing, but I won’t have to configure a static IP on my laptop or my server. I that interface use DHCP and wadaya know, I can access it on my 192.168.8.0/24 network now!

Since I can access the Proxmox web GUI now, I can get access to the command line of my OPNsense VM. If I configured this a bit differently, I could have gotten the OPNsense WAN interface on my travel router’s LAN, which would have had the benefit of being able to access the OPNsense GUI (since I port forwarded 443 like a month ago), but this has the advantage of being something I can leave like this long term (I can have this Ethernet port be an easy way to get into my machine for debugging).

Now that I’m into OPNsense’s shell, I can see that the WAN interface is doing just fine. I do not see the LAN interface when I boot in. Hmmm, I’m not sure how to enable the LAN interface without reconfiguring it, so I’ll just reconfigure. After putting in the interfaces for LAN, WAN, and OPT1, all my settings seem to be restored. Proxmox can talk to the outside world! Let’s see about other devices… Yep!

Note to self in the future: Don’t disable the LAN interface!!!