Linux tool for IPv6 unsolicited neighbor advertisements

ipv6linuxndp

Unsolicited neighbor advertisements is necessary to facilitate rapid service address takeover in a HA cluster. For IPv4 (ARP) you can use "arping -U", but so far I've had no luck finding any tool that can do something similar for IPv6.

EDIT:
After searching more maybe the question is: Is this tool needed for IPv6? To me it looks like NDP should be able to solve this by it self.

Best Answer

I've been investigating this too. So called Unsolicited Neighbor Advertisements are still required with NDP, see:

https://www.rfc-editor.org/rfc/rfc2461#section-7.2.6

On Debian based systems you can use ndsend which you can install as follows:

apt-get install vzctl

Related Solutions

Linux – List IPv6 Neighbor Proxies in Linux

Try with:

ip -6 neigh show proxy

It works for me:

emily ~ # ip -6 neigh add proxy 2001:db8:100:3022:1::4 dev eth0
emily ~ # ip -6 neigh show proxy
2001:db8:100:3022:1::4 dev eth0  proxy

Windows – Static IPv6 address in Windows unused for outgoing connections

The 'random address from the router' is probably your EUI-64 address, which is based on your MAC address. So it is probably not random and will stay stable over time (until you change hardware). Compare your MAC address to your IPv6 address. If your MAC address is 01:23:45:67:89:ab then your IPv6 address will end in ...:0323:45ff:fe67:89ab. You could add a PTR record for that address as well.

But I would like to suggest another solution: if you are sending mail directly to the receiver's mail server then you are running mail server software. You should be able to bind that server software to specific IP addresses. That way your mail server will always use the configured address when making outbound connections, while all other software can use whatever addresses are available on your host (static, autoconf, DHCPv6, privacy etc)

Best Answer

Related Solutions

Linux – List IPv6 Neighbor Proxies in Linux

Windows – Static IPv6 address in Windows unused for outgoing connections

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