I have 2 dedicated WAN connections for a VoIP only network and am having connectivity problems upon failover. Both WAN connections are static IP ( WAN1 = 50 x 5, WAN2 = 3 x 3)
Out of the box very basic setup:
Eth0 - WAN 1
Eth1 - WAN 2 (only failover if Eth0 down)
Eth2-4 - Switch 0 - 172.16.1.1/24
DHCP DNS 1 - 172.16.1.1
System DNS 1 - Public 8.8.8.8
System DNS 2 - Public 4.2.2.1
System DNS 3 - ISP DNS 1 (WAN 1)
Systems DNS 4 - ISP DNS 2 (WAN 1)
System DNS 5 - ISP DNS 1 (WAN 2)
Sytem DNS 6 - ISP DNS 2 (WAN 2)
When Eth0 goes down internet is confirmed working with a laptop + revealing WAN2 public IP is being used. Phones can place calls but not receive calls. The VoIP provider says the router is not flushing bindings properly and has instructed the end user to reboot the router followed by the POE switches. Is this a limitation of SIP or is there a fix I should seek in the router configuration?