NAT Internal Traffic

Is the FortiGate the default gateway for both VLANs? You said "firewall" but do you mean the FortiGate?

Hi,

Thank you for your reply. Yes Fortinet is using as gateway for both vlan's

Hi All,

Anyone can suggest what could be the problem.

Thanks 

Silver wrote:

Dear All,

Can someone tell me why for internal traffic do we need to enable nat in the policies.

Like example;

I have the following network 192.168.1.0/24 on vlan x and network 10.64.28.0/24 on vlan y. Both vlan's are using firewall as gateway and a sub interface configured with trunk to allow both vlan's. The problem if i do not enable nat on the policies both subnet cannot communicate. 

 

Thanks

sub interface configured with trunk to allow both vlan's.

There should 2 vlan subinterfaces acting as gw for both the vlans and those 2 should behave like normal interfaces. Where does the trunk come in?

Hello,

Does it happen with complete subnet or only specific hosts are tested?

- This looks to be more of a AV/Firewall on the end user or can be another L3 device which allows traffic only from the subnet it is connected to

Worth checking that part

Silver wrote:

Dear All,

Can someone tell me why for internal traffic do we need to enable nat in the policies.

Like example;

I have the following network 192.168.1.0/24 on vlan x and network 10.64.28.0/24 on vlan y. Both vlan's are using firewall as gateway and a sub interface configured with trunk to allow both vlan's. The problem if i do not enable nat on the policies both subnet cannot communicate. 

 

Thanks

Also, run debug flow or a simple sniffer command to see if the traffic exits the Fortigate on the egress VLAN or not.

Did someone find how what was the problem.
I'm having the same problem.
New setup with 3 interface only. WAN, Users, SRV.
Users are not able to get DNS query from the SRV subnet/interface without Nating enable.