Strange DNS Issue some site not accessable could be traffic route.

[Akbar_ali]

we have an issue in our DNS could be from fortigate, could be the traffic route not define correctly. The Scenario is

we have 2 ISP connections both are directly connected to Fortigate 100D version 5.4.5.1138. server subnet going to DIA link and PC subnet going to DSL link. but pcs are getting DNS from AD server. now the problem is i cannot access MSN, DHL and Turkishairline sites unless i use 8.8.8.8 or DSL gateway IP.

[CAD]

Add your ISP DNS in Forwarders(you find this option in DNS of doamin controller).

[Akbar_ali]

Actually the problem solved. as i explained i have 2 ISP so the pc traffic going through DSL and server traffic to DIA and in domain controller Forwarder configure for DIA DNS. which may be conflict. what i did i add DSL gateway as a Forwarder and create policy in fortinet under DSL interface so domain controller traffic can go through the same link where i need traffic.