No reply to NDP request from Linux host

Applications IP Networking
1

Hi, new here.

We are attempting to prove that an application will be able to carry IPv6. All is fine with IPv4 but not so much with IPv6. For now, we're just starting to ping between hosts to ensure basic communication.

I'll try to put as much info but of course feel free to ask for more.

Ping from Linux to Windows host:
NDP request is sent out, Window replies. Ping goes out. All is good.

Ping from Windows to Linux host:
NDP request is sent from Windows but linux host does not reply. We're stuck

Ping from Linux to Linux host:
NDP request is sent but linux host does not reply. We're stuck

So it might be as simple as a few kernel options we missed but we cannot figure which one. We are using Kernel 2.6.24. Yes, it is old. But nothing we've read seems to indicated that it cannot work on 2.6.24.

Any insight appreciated.

Lou

2

Troubleshooting IPv6 Networks and Systems

But maybe more to the point: IPv6-ready kernel

3

Thanks, we've gone mostly through this already.

Seems like the NDP is blocked somewhere as we don't even see in with TCPdump.

4

Nothing in firewall logs?

5

Hi, I am working on this issue as well with SavLou,

Iptables and ip6tables are usually used on Busybox for firewall rules, but they are not even installed / running on the hosts.
So no, no firewall logs�

The ICMPv6 NDP "neighbor solicitation" (type 135) is properly sent from host A as monitored on host C, but device B never gets any packet. All are connected on an IPv6 capable switch.

It is as if device B does not receive IPv6 multicast packets.