Troubleshooting Tip: Failure to configure a management interface with error 'IP address overlap with another interface'

Task:

In the following example: Port1 is enabled, has an IP address, and is being used to access the FortiADC 'SSH, GUI', and the FortiADC administrator needs to have Port1 configured as a dedicated management interface.

Advantages of using a dedicated management interface:

• Allows separate access of the Primary and Secondary in HA Active-Passive mode.

Prerequisites:

• Console access to FortiADC or SSH/GUI access through any interface except for the MGMT interface.

Error:

The administrator navigates to Network -> Interface and enables the Management Status for Port1, but receives the error 'IP address overlap with another interface'.

Solution:

1. Remove the IP address assigned to port1 [Management access will be lost if Port1 is the GUI access port]:

2. Access FortiADC through a console or any interface other than Port1.
3. Configure Port1 as a dedicated management interface:

config system ha
    set mgmt-status enable
    set mgmt-interface port1

    set mgmt-ip 10.120.19.78/20

    set mgmt-ip-allowaccess https ping ssh snmp http telnet
end

Related article:

Configuring the management interface - FortiADC 7.4.7 handbook