=== Accept Multicast and Broadcast packets on iptables ===

\\
Adapt to your needs:
<code bash>
iptables -A INPUT -i eth0 -m pkttype --pkt-type multicast -j ACCEPT
iptables -A INPUT -i eth0 -m pkttype --pkt-type broadcast -j ACCEPT
</code>

Some sources:

https://serverfault.com/questions/325652/how-to-make-iptables-allow-rule-for-multicast