Comment on Setting Up OPNsense on Proxmox: Doubts regarding NIC setup
xavier666@lemmy.umucat.day 2 weeks ago I have one more doubt.
(Nothing setup as of now, just checking all possible angles)
Since, as per your suggestion, I have passed the NIC to OPNsense, so Proxmox won’t see the dual NIC card.
The onboard ethernet port eth3 is connected to a switch and Proxmox will use eth3.
Image Here’s a fresh diagram
You can see that I have a Ubuntu VM. How will the PC communicate with the VM? (Links E and D are hypothetical. I don’t know which one is better given my scenario). Will it be C -> B -> D or C -> A -> E?
Case #1: C -> B -> D
The switch must differentiate between uplink traffic/proxmox traffic/other physical devices connected to the switch (phone/TV). I prefer this solution because even if OPNsense is down, I can still access the Ubuntu server. But the switch must handle this complexity. I will be getting a managed switch anyway.
Case #2: C -> A -> E
The interface eth2, which OPNsense is using, must have some sort of routing table which redirects to links E or F depending upon destination IP (Probably implemented using virtual bridge or virtual switch). This is simpler for the switch but if OPNsense is down, i lose direct network access to the VM. I can probably access it via Proxmox web-interface.
Can you tell me which one is preferred or which one you would have done?
Sorry for my ramblings.
NarrativeBear@lemmy.world 2 weeks ago
Lines F and E don’t exists in your diagram, all your VMs inside of Proxmox are accessible and sharing port eth3. Except Opensense, as its not bridged to eth3, but instead is assigned to the NIC card you have.
OPNSense inside Proxmox is the only VM that will see the NIC card and be the only VM that uses that NIC with those interfaces.
One interface would be for WAN in like you drew, and the other is the LAN port like on any other router. This LAN port needs to connect to a switch as this is where your OPENsence will communication with the rest of the home network and handout DHCP addresses. It’s also how you would reach your OPENsense GUI through a browser. (Outside of managing it within Proxmoxs GUI, accessible on eth3)
If your OpenSense VM goes down your home network won’t have a router which means no PCs would be able to communicate as they would have no DHCP addresses, so even if all your communication is “inside of Proxmox” your VM still would not get a DHCP addresses.