Restrict WebGUI Access to host IP or by mac adress

[salvador fx]

Is there a manual or exemples to restrict WebGUI Access to host(s) IP or by mac adress, only inside LAN?
I found some but for pfsense. Propably it´s the same...

[errored out]

There are a few ways I can think of. 

1) Configure a FW rule blocking all traffic to your firewall management IP&port.  If wanting to configure by MAC, you could set your DHCP server to assign a specific IP to your management computer (Services: DHCPv4 > DHCP Static Mappings for this interface). 

2) Create another VLAN, create FW rules only allowing your management computer IP&port to access the new VLAN.