In gateway group, WAN or WAN2 randomly drops and stays offline until reboot

[patrick3000]

I have OPNsense set up with a gateway group, with two interfaces, WAN and WAN2, connected via cable modems to the public internet and getting IPV4 addresses assigned by DHCP.

Unfortunately, sometimes either the WAN or WAN2 interface will randomly drop and go into offline status, even though there is no internet outage. When this happens, the interface stays offline until I reboot OPNsense. Since it's a gateway group, I sometimes don't even know that WAN or WAN2 went offline since I still get internet from the other interface in the group. However, I am now in the habit of checking the OPNsense dashboard every couple of days to see if either WAN or WAN2 has gone offline.

Currently, I am running OPNsense virtually, as a guest VM over KVM in Truenas SCALE. However, until a few months ago, I had OPNsense installed bare metal on a physical computer, and I still had the same problem with intermittent random drops of either WAN or WAN2, so I don't think this problem has anything to do with virtualization.

Also, I have tried to simulate the problem and cannot do so. To attempt to simulate it, I disconnect the coax cable leading to the modem for either WAN or WAN2, and OPNsense correctly shows the interface going offline. Then, when I connect the coax cable to the modem again, OPNsense correctly shows the interface as online.

Does anyone know anything about this? Have you had it happen, or do you know how to troubleshoot it?

[FraLem]

The status of the interface is monitored by sending a ping packet to the Ip address defined on the gateway, which IP address are you using on the offline interface. Can you try to ping this IP when it goes down?

Rgds