There are times when you might need to filter the traffic on your firewall using MAC addresses instead of IP addresses, iptables has the option to do it.

From the man page of iptables:

Note that this only makes sense for packets coming from an Ethernet device and entering the PREROUTING, FORWARD or INPUT chains.

If you have a network of Linux Fedora, maybe you want to save bandwidth by creating your own repo on your local network. Here is how.