Configure Routing for VoIP and DATA over 2 WAN IP's

Question

I am hoping for some assistance in configuring XG125 for use with 2WAN IP's, one for Data one for VoIP. 
 
 Currently, traffic is flowing correctly for the DATA network, through WAN 1 (port 2 on XG) 
 
 I have another WAN interface (WAN 2 - Port4) for VoIP traffic, using a separate ISP from the DATA network, which I have taken from the initial br0 bridge pair 
 My Phones system comes from a device on the LAN with the IP 172.20.164.190, and I need all traffic from that IP to be routed through WAN2. 
 I then need the incoming traffic from WAN2 port to be accepted, and forwarded to that device on my LAN using a set of TCP and UDP ports. 
 
 Do I need to create a new LAN zone for the device in question? 
 Which firewall rules are needed to route the correct traffic through the correct gateway. / User/Network rule or Full NAT? 
 Do I need to create Policy Routes? 
 
 VoIP currently working through Draytek but need to move it over to the XG.

Alex_B81 · Answer

HI All 
 
 Had time over the weekend to finalise config. 
 First change that was made was to disable SIP ALG on the XG. 
 Second, with the assistance of Riley at Sophos, new rules were created as follows: 
 
 Inbound: Business Application Rule 
 Source: WAN 
 Allowed Networks: ANY 
 Destination host/network: #Port4 (my WAN 2 port) 
 Services: VoIP Services group with the required ports 
 Forward to: My VoIP server in LAN 
 
 Had to disable Masquerading (the initial rule was with Masquerading however incoming calls stopped working after about 20 mins) and unchecking masquerading has since helped. 
 
 Outbound: User/Network Rule 
 Source: LAN 
 Source networks/devices: VoIP Server 
 Destination Zone: WAN 
 Destination Networks and Services: ANY 
 
 NAT & Routing: checked rewrite Source Address 
 Outbound Address MASQ 
 Primary Gateway: WAN2 port 
 
 Updated the default network firewall rule to use WAN1 as the primary gateway as the default was set to WAN link load balance

Aditya Patel · Answer

Hello Alex, 
 If you have 2 WAN links configured on your firewall. You could create a network/user rule to allow the traffic to your VOIP server. I believe your VOIP server has an IP address or URL it connects to. You may create a destination based rule using an IP address or FQDN rule using a URL . Apply NAT MASQ and configure your primary gateway on that firewall rule as the link on WAN2 and backup as WAN1.