See KB
Your failover group has no ping target configured....so it falls back to using ping.ubnt.com......which is unknown when both WAN links are down for some time.
Use static IP addresses instead, like each provider DNS server
See KB
Your failover group has no ping target configured....so it falls back to using ping.ubnt.com......which is unknown when both WAN links are down for some time.
Use static IP addresses instead, like each provider DNS server