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Last active February 2, 2024 14:33
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Allow multicast communications in iptables
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iptables-multicast.sh
Run the following:
iptables -A INPUT -m pkttype --pkt-type multicast -j ACCEPT
iptables -A FORWARD -m pkttype --pkt-type multicast -j ACCEPT
iptables -A OUTPUT -m pkttype --pkt-type multicast -j ACCEPT
Or:
iptables -A INPUT -s 224.0.0.0/4 -j ACCEPT
iptables -A FORWARD -s 224.0.0.0/4 -d 224.0.0.0/4 -j ACCEPT
iptables -A OUTPUT -d 224.0.0.0/4 -j ACCEPT
@dacianstremtan
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Change this INPUT chain to allow inputs with the multicast destination

iptables -A INPUT -d 224.0.0.0/24 -j ACCEPT
or limit to multicast request from your own network only:
iptables -A INPUT -s <your_private_network_cidr> -d 224.0.0.0/24 -j ACCEPT
where <your_private_network_cidr> can be something like 192.168.1.0/24

@kobtsev-m
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Thanks a lot!

@hungkien05
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hungkien05 commented Jan 18, 2022 •
edited

image

My network topology is shown in the picture. H1 will send multicast packet to H2 through R1 and R2. Which iptables rules should I set at R1 and R2 ?
Thanks in advance !

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