Multiwan not switching properly on ungraceful connection loss

[schmuessla]

Hi all,

I'm currently trying to setup Multiwan with failover. My primary connection is a DSL line with PPPoE and dynamic v4 adresss + dynamic v6 prefix. The fallback connection is a mobile router with v4 only connections where the router acts as a gateway.
If I manually click "disconnect" on Interfaces -> Overview of the primary interfaces, OPNSense correctly deprecates the not anymore existing v6 prefix and everything is routed via v4 using the mobile router.

However, if I simulate an external connection loss by pulling out the cable which establishes the PPPoE session, OPNSense properly detects that the gateways are down but the prefix is not deprecated. Additionally Unbound also seems to have problems then because it returns empty results for new DNS requests.

Did I miss any setting to get this working properly or is it just a bug?