I have two wireless networks, one guest network which uses a 10.0.0.0 network to assign IP address to guests and one internal one who gets the IP address from the internal DHCP (let's say 192.168.0.0/24).
Guest WiFi also uses an external DNS server. As of now, Guests and Internal networks are completely separate.The Meraki AP uses NAT to translate 10.0.0.0 packets the internal IP of the AP (192.168.0.10)and sends them to the FW (192.168.0.1) to be forwarded again to wherever they need to go.
One problem I have is that because the Guests are using an external DNS server, when they want to access their company mail (on their personal phones), the packets are being sent to the external IP address of the exchange mail server (lets say 220.127.116.11) on the FireWall (from 192.168.0.10, the APs IP address) and at the SonicWall FW, the packets are being dropped.
Looking at the firewall rules, I see that all packets coming from the internal subnet to the WAN area are allowed. Why do you think the packets are dropped even if the rules allow it? I'm suspecting it is an internal routing issue of the firewall. Can any one think of a trick to allow the packets back in?