Operating modes and VDOMs
To use WAN optimization, the FortiGate units can operate in either NAT/Route or Transparent mode. The client- side and server-side FortiGate units do not have to be operating in the same mode.
As well, the FortiGate units can be configured for multiple virtual domain (VDOM) operation. You configure WAN optimization for each VDOM and configure one or both of the units to operate with multiple VDOMs enabled.
If a FortiGate unit or VDOM is operating in Transparent mode with WAN optimization enabled, WAN optimization uses the management IP address as the peer IP address of the FortiGate unit instead of the address of an interface.
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