Filter MAC Addresses comming into WAN port

Greetings everyone,

Im doing some experiments on my lab, and i cant get to an acceptable result yet, now i have the following scenario:
acessoRemoto (2).png
4G antenna → rb750GR3/eth1 → server on internal network(eth2-5)

THE GOAL: get information from some internal servers outside the network.

IMPEDIMENTS:
I cannot use a VPN
I cannot add authentication (user & pass) to the servers, because i dont have acess to the software

MY SOLUTION (incomplete):

  • I have done a port forward (dst-nat) to the servers, but now i want to filter the MACs that can communicate with them
  • Created an Address List name:allowedGroup with the MAC addrs that i want to do the communication
  • Added the first filter rule: action:accept , chain:forward , in.interface:eth1, dst.addresses:allowedGroup
  • Added the second filter rule: action:drop , chain:forward , in.interface:eth1, dst.addresses:!allowedGroup

but the filter rules are not working

There is any way of restrict the acess to this servers, and still use the port forwarding ?