====== Ebtables ======
===== Nat =====
<code bash>
ebtables -t nat -A PREROUTING -d 00:11:22:33:44:55 -i eth0 -j dnat --to-destination 54:44:33:22:11:00
</code>

This will make all frames destined to 00:11:22:33:44:55 that arrived on interface eth0
be transferred to 54:44:33:22:11:00 instead.
As this change of destination MAC address is done in the PREROUTING chain of the nat table,
it is done before the bridge code makes the forwarding decision.

<code bash example.sh>
int_if=zeoip2
int_mac=00:1A:D0:11:5F:18
ext_if=eth0
ext_mac=00:02:9B:93:AC:EA

ebtables -t nat -A PREROUTING -d $ext_mac -i $ext_if -j dnat --to-destination $int_mac
ebtables -t nat -A POSTROUTING -d $int_mac -i $int_if -j snat --to-destination $ext_mac
</code>