Instances won't obtain IPv6 address and gateway when using SLAAC provided by OpenStack

[Nir Magnezi]

Description of problem:
=======================
I Created an IPv6 subnet with:
1. ipv6_ra_mode: slaac
2. ipv6_address_mode: slaac

Version-Release number of selected component (if applicable):
=============================================================
openstack-neutron-2014.2-0.7.b3

How reproducible:
=================
100%

Steps to Reproduce:
===================
1. create a neutron network
2. create an IPv6 subnet:
# neutron subnet-create <IPv6_net_id> 2001:db1::/64 --name usecase1_ipv6_slaac --ipv6-address-mode slaac --ipv6_ra_mode slaac --ip-version 6
3. boot an instance with that network

Actual results:
===============
1. Instance did not obtain IPv6 address
2. default gw is not set

Expected results:
=================
The instance should have IPv6 address a default gw configured.

[Nir Magnezi (nmagnezi)]

Looks like this issue is a result of: https://bugs.launchpad.net/neutron/+bug/1377985

[Sergey Belous (sbelous)]

The bug is not fully reproducible. I launched cirros and ubuntu instance in ipv6-subnet (ipv6_ra_mode: slaac ipv6_address_mode: slaac) and instances obtain ipv6 address. But still default gw is not configured for instances launched in ipv6-subnet.

[Sergey Belous (sbelous)]

@nmagnezi, Did you connect ipv6-subnet to router? For obtain ipv6 in subnet SLAAC-mode, it need to be connected to router.

[Sean M. Collins (scollins)]

You must attach a router to the network when ipv6_address_mode is set to "slaac" for instances to get addresses. You specified via the API that you want openstack to use stateless auto address configuration, and that requires a router to transmit RAs.