The default FortiGate-7000 configuration includes a management VDOM named mgmt-vdom. The management interface (mgmt) and the HA heartbeat interfaces (M1 and M2) are in this VDOM. You cannot delete or rename this VDOM. You also cannot remove interfaces from it or add interfaces to it. You can however, configure other settings such as routing for management communications, the mgmt interface IP address, and so on.