Troubleshooting

Let's look at some of the common issues while configuring load balance and failover configurations:

• Failover/load balance isn't working: The tier 1 WAN line goes down, but the traffic is still trying to leave the firewall through it. OPNsense, by default, will set the gateway's IP address as the monitor IP address; for instance, let's suppose the WAN line was interrupted somewhere between the customer and the Internet Service Provider (ISP). The router/modem will be still alive and responding to ICMP requests. This can happen because the gateway's IP address is the local network interface of the router/modem, and it won't be down in this case, so the OPNsense monitoring daemon will consider it online; therefore, the condition to change to another WAN will not be triggered. To avoid this issue, always set the monitor IP address to an ISP WAN's cloud address; this way, when the communication between the ISP's router/modem...