DHCP client mode for inter-VDOM links

Continuing with the same configuration as Example GUI configuration, a new VDOM named lan-extvdom was created on the FortiGate Connector and its type was set to LAN extension. This configuration allows the VDOM to function as a FortiExtender in LAN extension mode. However, it should be noted that this configuration results in the loss of FortiGate security features on that VDOM. For users who wish to utilize the security features of the FortiGate locally on the FortiGate Connector, another VDOM, such as the root VDOM, can be used.

Once the DHCP server is enabled on the FortiGate Controller (as shown in step 2 of Example GUI configuration), an inter-VDOM link belonging to another VDOM (in this case, the root VDOM) can receive an IP address by DHCP from the FortiGate Controller.

In this topology, the DHCP clients on the FortiGate Connector interact with the different DHCP servers on the FortiGate Controller.

• The port3 IP address is obtained by DHCP from the FortiGate Controller DHCP server on the port3 connected interface.
• The lan_ext1 IP address is obtained by DHCP from the FortiGate Controller DHCP server on the LAN extension interface.

To configure DHCP client mode on the inter-VDOM link on the FortiGate Connector:

1. Add the VDOM link with an Ethernet type:

   config system vdom-link
       edit "lan-extvdom"
           set type ethernet
       next
   end

2. Configure the VDOM link interfaces:

   config system interface
       edit "lan_ext0"
           set vdom "lan-extvdom"
           set role lan
       next
       edit "lan_ext1"
           set vdom "root"
           set mode dhcp
       next
   end

   Since lan_ext0 has its role set to lan, this interface is added to the le-switch software switch in the lan-extvdom VDOM. This software switch provides network connectivity to the LAN extension clients (in Example GUI configuration) and the root VDOM clients (in this example) through the FortiGate Connector LAN extension VXLAN aggregate link.

3. Verify that the lan_ext1 interface obtained an IP address from the FortiGate Controller (the client IP address for the lan_ext1 VDOM link is from the same 192.168.0.0/24 subnet in step 10c of Example GUI configuration):

   Connector-FGT (lan-ext) # diagnose ip address list | grep lan_ext1
   IP=192.168.0.1->192.168.0.1/255.255.255.0 index=30 devname=lan_ext1