Next time check in System > Routes > Status, if you have a default route set
Some devices (modems, etc.) have a feature in that they stop responding if they have not received an ARP request for a couple of minutes. The cache of BSD based routers (such as OPNSense) is longer than that. Try adding net.link.ether.inet.max_age=120 to tunables, which forces the router to re-arp every two minutes and often solves this issue.
What do the logs say? This seems like a DHCP lease expiring on WAN and not renewing until the interface is force reloaded.Is there anything in System/Log Files/General around the timeframe that the WAN link becomes unresponsive?
2024-06-05T17:51:46 Notice kernel <3>arp: d0:50:99:f6:xx:xx is using my IP address xx.xx.127.59 on vtnet0!
Is the MAC from your modem?I have the same error on my box (with different MAC/IP) with MAC from my Starlink Router since changing to 24.x, however, this is not true. Starlink Router does hold the MAC but _not_ the IP!?It is not affecting me in any case as far as I can see, though.
How is proxmox configured for the OPNsense NICs? Are you using direct hardware passthrough or is there a virtual switch with virtual interfaces assigned to the OPNsense VM?If it's using a virtual switch, is there another device on the OPNsense WAN side that is 'stealing' the DHCP address?
That all seems logical and correct. The phantom MAC that is stealing the WAN IP, does that MAC coincide with the IPMI interface? I'd want to be extra sure that isn't somehow popping up on the NIC that proxmox is using for the WAN bridge and causing all kinds of issues. I know this is apples/oranges but some newer HP server hardware allows the lights out functionality "move" around to different NICs, so I'm not sure if Asrock has a similar function or not?The other odd issue that might be worth checking is newer mainboard BIOS' have the option for "install drivers" or some such feature. This usually involves the BIOS UEFI firmware pulling an IP address and trying to stage drivers through to the OS. If your mainboard has such a feature I would suggest turning it off and see if this may also be using that ENO1 NIC for those attempts. This is a long shot but I'm just thinking out loud here trying to help narrow down possibilities.
I know this is apples/oranges but some newer HP server hardware allows the lights out functionality "move" around to different NICs, so I'm not sure if Asrock has a similar function or not?
also if proxmox is the OS on the host, list the interfaces $ip aCan you check the networking setup of your other VM ? If the MAC in the list appears there, then it could be the VM causing the clash. Maybe some software there could also be worth visiting.