[HowTo] Setup MAC address filtering on FreeBSD

To enable MAC address filtering in FreeBSD first you need get MAC addresses for all clients which you want to give internet access.
To get MACs I suggest use FastResolver. You need to run it any computer located in your network. Also You can run

# arp -a

in your router.

After that edit ethers file

$ vi /etc/ethers

and add ip and MAC address list like:

192.168.2.1	00:00:00:00:00:00

192.168.2.2	00:00:00:00:00:00

192.168.2.3	00:00:00:00:00:00

192.168.2.4	00:00:00:00:00:00

192.168.2.5	AB:CD:AB:CD:AB:CD

Use 00:00:00:00:00:00 for that IP addresses which should not have access to internet.
Next step is to delete the current configuration of ARP entries:

$ arp -ad

And finally load the configuration file:

$ arp -f /etc/ethers