Internet issue of clients

[Mohammed_f]

Dears all 

I have an issue of our company site. 

We have 3 isp link contact to fortigate 300 e to spart port using SDWAN, the firewall can ping the Internet, we make a policy allow LAN network to internet, everything is fine, clients can ping 8.8.8.8, and can reach the gatway but can not access to email Outlook and brosing the Internet. 

I check the DNS Server it is big to gatway and internet, but in clients pc I make ipconfg/all

The DNS Take ipv6 

With different DNS not AD, 

How Can I solve this issue 

[parteeksharma]

Hi Mohammed_f

Please let us know the below:

==> Does the PC getting the IP address and dns settings from the DHCP server ?

==> Does fortigate acts as DHCP server in your network ?
==> Does all the users are facing the issue or a group of user?

Regards,
Parteek

[Mohammed_f]

The pc get ips from the dhcp Server 

The fortigate act as gatway and only firewall not dhcp Server 

Group of Users face This issue 

[gfleming]

You need to ensure your DHCP server is assigning the correct DNS servers to your clients. Please check your DHCP server configuration.