Comment 6 for bug 1808647

Ryan Harper (raharper) wrote :

The log looked a bit strange, it shows cloud-init 0.7.9, not 18.2. In any case, it still reproduced on master. The provided network-config is to dhcp4 and dhcp6 on the primary interface.

Looking at what IPV6_AUTOCONF boolean controls, I see:

IPV6_AUTOCONF=answer
where answer is one of the following:
yes — Enable IPv6 autoconf configuration for this interface.
no — Disable IPv6 autoconf configuration for this interface.
If enabled, an IPv6 address will be requested using Neighbor Discovery (ND) from a router running the radvd daemon.
Note that the default value of IPV6_AUTOCONF depends on IPV6FORWARDING as follows:
If IPV6FORWARDING=yes, then IPV6_AUTOCONF will default to no.
If IPV6FORWARDING=no, then IPV6_AUTOCONF will default to yes and IPV6_ROUTER has no effect.

We don't currently provide a way via network-config to control IPV6_AUTOCONF nor IPV6FORWARDING and it's not clear that there is a default value in sysconfig either. Historically the IPV6_AUTOCONF=no was set expecting that the provided networking would include any gateway values if needed.

It's not clear to me why dhcp6 does not get you a gateway? Can you provide the dhcp6 lease and 'ip -6 a' and 'ip -6 route show' output?

I;d like to understand what does and does not work with IPV6_AUTOCONF enabled/disabled.