Technical Tip: FortiGate dedicated-mgmt feature, or Out-of-band Management
Description
- Reserving an interface in HA for individual management of FortiGates (up to 4 interfaces).
- On select models, a separate interface can be configured with 'dedicated-mgmt' interface/routing.
This article refers to the second method. Discussion of the HA reserved management interface is left to other reference documents, including the article: Technical Tip: HA Reserved Management Interface.
For example, if using the wan1 port as the primary port for management, and the dedicated-mgmt feature is enabled by using for example mgmt1 port for out-of-band management, there will be a redundant management port, which is useful if the port wan1 becomes unavailable.
Scope
This feature is available on models with mgmt/mgmt1/mgmt2 ports, such as the following:
- FortiGate-100F/101F.
- FortiGate-120G/121G.
- FortiGate-200F/201F.
- FortiGate-400F/401F.
- FortiGate-600F/601F.
- FortiGate-900G/901G.
- FortiGate-1000F/1001F.
- FortiGate-3000F/3001F.
- FortiGate-3200F/3201F.
- FortiGate-3500F/3501F.
- FortiGate-3700F/3701F.
- FortiGate-4800F/4801F.
- FortiGate-6000F.
- FortiGate-7000E/7000F.
- FortiWIFI-1801F.
- FortiWIFI-2600F.
- FortiWIFI-3980E.
- FortiWIFI-4200F.
- FortiWIFI-4400F/4401F.
- FortiWIFI-4801F.
- FortiWIFI-3980E.
Solution
set status {enable | disable}
set interface [mgmt | mgmt1 | mgmt2 ]
set default-gateway x.x.x.x
set dhcp-server {enable | disable}
set dhcp-netmask
set dhcp-start-ip
set dhcp-end-ip
end
set ip 10.24.3.199 255.255.252.0
set allowaccess ping https ssh http telnet
set type physical
set dedicated-to management
set role lan
set snmp-index 27
next
end
execute enter dmgmt-vdom
current vdom=dmgmt-vdom:3
get router info routing-table all
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
V - BGP VPNv4
* - candidate default
Routing table for VRF=0
S* 0.0.0.0/0 [10/0] via 10.24.3.200, mgmt1, [1/0] <-- Default route via mgmt1 created in dmgmt-vdom.
C 10.24.0.0/22 is directly connected, mgmt1
Note:
There is a known issue with the dedicated-mgmt feature in HA deployments. When a device newly joins an HA cluster where the primary unit already has the dedicated management interface enabled, the joining unit may lose the MGMT interface itself. As a result, the interface will no longer be visible in the system configuration, and CLI commands or diagnostic commands related to the MGMT interface cannot be executed.
For example:
show system interface mgmt
entry is not found in global table
diagnose hardware deviceinfo nic mgmt
Command fail. Return code -1
This issue has been resolved, and the fix is available in FortiOS versions 7.4.9, 7.6.4, 8.0.0, and above.
config system dedicated-mgmt
set status disable
end
config system interface
edit "mgmt1"
set vdom "root"
set vrf 1
set ip 10.24.3.199 255.255.252.0
set allowaccess ping https ssh http telnet
set type physical
set dedicated-to management
set role lan
set snmp-index 27
next
end
config router static
edit 0
set gateway 10.24.3.200
set device "mgmt1"
next
get router info routing-table database
Routing table for VRF=1
S *> 0.0.0.0/0 [10/0] via 10.24.3.200, mgmt1, [1/0]
C *> 10.24.0.0/22 is directly connected, mgmt1
The 'dedicated-to management' feature:
Setting an interface as 'dedicated-to management' can be done in the GUI as well as the CLI. However, this is a different function from dedicated-mgmt configuration.

config system interface
edit mgmt
set dedicated-to management
next
end
Note:
When configuring a VM FortiGate, use this article, Technical Tip: HA Reserved Management Interface when configuring the VM due to a limited number of available interfaces.
When an interface is set to 'dedicated-to management', the settings with this interface will be synced between the Primary and the Secondary units. This is different than the HA dedicated management interface, which is NOT synced between the Primary and the Secondary units.
Related article:
Technical Tip: FortiGate SNMP polling via the dedicated HA management port - HA status MIB OID
