pfSense

there are two internet router members added to a Gateway Group. one router (4G wireless modem) became unregistered from the 4G network and was not able to pass traffic to the internet, but pfSense continued to show this network as "online" and continued to send DNS resolution requests to this member and continued to rout traffic to this member with no success. users were randomly not able to access the internet until the group was deleted and the problematic WAN was disabled.

the trigger criteria was "high latency or packet loss" but i believe member down would have failed also.

additionally, i had to uncheck "Allow DNS server list to be overridden by DHCP/PPP on WAN" and manually assign DNS servers on the working router because pfSense also continued to send DNS requests to the affected router even AFTER i deleted it.

i dont know what exact parameters are used to detect if a router is offline but the router WAS online but not able to route to the internet. maybe it would be beneficial to have an advanced area where i can specify a few hosts, interval and consecutive failure threshold for the purpose detecting an actual offline state. or use a trace route to detect the next upstream hop to use as a detector would be cool also.