IPv6 requires ICMPv6 neighbour solicitation and neighbour advertisement packets to create IPv6 connectivity. These packets are used to resolve IPv6 addresses to link-layer (ethernet).
- Add new icmptypes for
neighbour solicitationandneighbour advertisement
firewall-cmd --permanent --new-icmptype=neighbour-solicitation
firewall-cmd --permanent --new-icmptype=neighbour-advertisement
- Remove destination IPv4
firewall-cmd --permanent --icmptype=neighbour-solicitation --remove-destination=ipv4
firewall-cmd --permanent --icmptype=neighbour-advertisement --remove-destination=ipv4
- Attach icmptypes to the –zone=drop list of –add-icmp-block
firewall-cmd --permanent --zone=drop --add-icmp-block=neighbour-solicitation
firewall-cmd --permanent --zone=drop --add-icmp-block=neighbour-advertisement
- Invert the icmptype block.
firewall-cmd --permanent --zone=drop --add-icmp-block-inversion
Confirm icmp-block-inversion from output of following command.
firewall-cmd --permanent --list-all --zone=drop