Hi.
I've got a Draytek 2860 on latest firmware, with leased line WAN2 and USB 4G modem (supported) on WAN3 set as failover.
The failover works almost instantly and is a dream for all normal IP traffic from PCs.
However, the VoIP phones do not reconnect/reregister with the VoIP provider (Voipfone) - they just sit there saying unregistered. Rebooting phone makes no different.
(I left it 5-10m but had to go back to primary internet as no one was getting calls and you know, users lol).
Voipfone do not have IP restrictions, so its not that. The 4G network does allow VoIP traffic and this works fine (with same handsets and provider on other routers/modems, eg. Ubiquiti Edgemax +external 4G modem.
So its not a concept or provider issue, but probably a draytek setting.
ALG is off. But QoS is on. Am I missing a setting? Does the Draytek need to...