[CentOS] Diagnosing IPv6 routing

Tue Apr 28 23:22:16 UTC 2020
Chris Adams <linux at cmadams.net>

Once upon a time, Kenneth Porter <shiva at sewingwitch.com> said:
> On 4/28/2020 3:17 PM, Chris Adams wrote:
> >- gateway sends a router solicitation and gets a router advertisement
> >   with "stateful config" set, which tells gateway to do DHCPv6 (but
> >   default route comes from RA)
> I'm not seeing any outbound IPv6 traffic from my CentOS 7 box on the
> WAN interface. I do see RA's emitting from the LAN interface, from
> radvd. Is there some setting in NM tells it to send solicitations?
> Is there some way to push one manually?

What's in /etc/sysconfig/network-scripts/ifcfg-<name>?  I wonder if you
have IPv6 disabled.

I'm not using a "regular" (CentOS, Fedora, etc.) Linux as a gateway; I
have OpenWRT on a dedicated box.  I couldn't find a way to handle the
prefix delegation with the typical desktop/server tools (but it has been
a while since I looked).  OpenWRT has their own daemon for that.

However, my local systems are all sending RA solicitations and getting
DHCPv6-assigned addresses with NetworkManager (which matches the first
steps of what you need on the WAN, just not the prefix delegation).

Chris Adams <linux at cmadams.net>