Questions tagged as ['icmpv6']
I have a Debian 11 VPS on a cloud provider, with both IPv4 and IPv6 enabled and the eth0 interface with both a global-scoped ipv6 address (public) and a link-scoped ipv6 address (fe80::/10).
The sole purpose of the server is to host a public website.
I’m implementing a firewall on the server using iptables/ip6tables. I read RFC4890 but still not sure how to handle some ICMPv6 message types and if ...
I have some Netflow records from a bunch of routers. The records contain IPv6 flows and there are entries with protocol as ipv6-icmp and their destination port values as 0, 1025 and 257. I know from this link that the value of 0 for ipv6-icmp in netflow indicates an echo reply. Is there any resource to find the meaning of the ipv6-icmp-1025 and ipv6-icmp-257?
In summary, how can I force an interface to use the global IPv6 address as the source for neighbor solicitation messages rather than the link address?
Background: Many VPS providers do not allocate a routed IPv6 /64 but merely assign a block on a /48. The gateway is a global IPv6 address on the /48 but outside the /64. The gateway responds to NS messages sent from a global address, but does not re ...