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Article Id 193539
This article explains how to use out-of-band management on standalone unit without using VDOMs.

Unit should use dedicated management interface for management and should connect to the Internet through this management interface for all management traffic.

The unit is a standalone unit (not in HA) and the usage of multiple VDOMs (split-task VDOM) is not intended.

The solution is to use different VRFs (Virtual Routing and Forwarding) for management and for the traffic.

Each FortiGate unit can use several VRFs. By default, all interfaces and routes are in VRF 0.
This also applies to the management traffic.

When it is required to route the management traffic through the different gateway, then normal traffic with different VRFs can be used.

This must be configured in CLI.

Management interface should stay in VRF 0 and all other interfaces that are used for traffic should be configured to the other VRF (for example 1).
#config system interface
edit wan1
set vrf 1
edit port1
set vrf 1
Then two default routes can be configured:
#config router static
    edit 1
        set gateway
        set device "mgmt"
    edit 2
        set gateway
        set device "wan1"
The output of the routing table:
FGT # get router info routing-table all
Routing table for VRF=0
Codes: K - kernel, C - connected, S - static, R - RIP, B - BGP
       O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
       * - candidate default
S* [10/0] via, mgmt
C is directly connected, mgmt
Routing table for VRF=1
S* [10/0] via, wan1
C is directly connected, wan1
C is directly connected, port1

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