vm did not acquire an ipv6 stateful address

[Senthil Mukundakumar]

Brief Description
-----------------

VM did not acquire an ipv6 stateful address with ipv6 subnet

Severity
--------
Major

Steps to Reproduce
------------------
- Lab is ipv4 lab as default
- Run lab setup
- Deleted subnet of tenant1-net9
- neutron subnet-create --ip-version 6 --ipv6-ra-mode dhcpv6-stateful --ipv6-address-mode dhcpv6-stateful --dns-nameserver 2001:4860:4860::8888 tenant1-net9 fd00:0:0:21::9/64
- Boot an VM with the above modified network
- Login to vm,
vi /etc/sysconfig/network-scripts/ifcfg-eth0, change IPV6INIT=yes, add DHCPV6C=yes
vi /etc/sysconfig/network, add NETWORKING_IPV6=yes
systemctl restart network

Expected Behavior
------------------
VM should get an IPV6 assigned to the interface inside guest

Actual Behavior
----------------
VM did not get ipv6 address assigned

Reproducibility
---------------
Reproduble (3/3)

System Configuration
--------------------
Any system

Branch/Pull Time/Commit
-----------------------
StarlingX_18.10 2018-10-11_01-52-00

TIME STAMP:
2018-10-16 16:10:50.498

[Ghada Khalil (gkhalil)]

Targeting stx.2019.03 - ovs-dpdk validation has not been done for IPv6; not surprised that there are issues. Not required for stx.2018.10 as the focus has been on IPv4

[Ghada Khalil (gkhalil)]

Further testing of ovs-dpdk with IPv6 has exposed serious issues. See attachment for further details.

Note: IPv6 support is a late add to ovs/ovs-dpdk, so it's unclear how much testing has been done in the community. There is nothing specific to StarlingX that explains these issues and it's likely they are available in upstream as well.

No plan to investigate further or address at this time.