When ovn/dns_servers consist of IPv6 dns nameservers,
it was getting added to IPv4 dhcp options also, and due to
this an invalid nameserver(last 4 octets of an IPv6 address)
is set in the instances.
This patch filters IPv4/IPv6 dns nameservers and set
dhcpv4/dhcpv6 options accordingly.
Also when dns_nameservers are not set for IPv6 subnets,
get those from ovn/dns_servers config or system nameservers
just like it's done with the IPv4 subnets. Updated
get_system_dns_resolvers to pick both IPv4/IPv6 valid
ips, this also requires bump of oslo.utils minimum version
to 4.8.0 to use strict option for IPv4[1].
Additionally fix some unit tests which were setting IPv4 dns
nameservers on the IPv6 subnets, this is not allowed with api.
[1] https://github.com/openstack/oslo.utils/commit/3288539
Conflicts:
lower-constraints.txt
requirements.txt
[Stable Only] Since Neutron stable policy do not allow bumping
of minimum version of a requirement in stable releases, so doing
a partial backport by not backporting requirements.txt changes and
updated get_system_dns_resolvers to work with older version of
oslo.utils.
Depends-On: https://review.opendev.org/c/openstack/neutron-tempest-plugin/+/826647
Closes-Bug: #1951816
Change-Id: I9f914e721201072e43a8c6c266ed97ca85fcc13d
(cherry picked from commit 4a06685098)
(cherry picked from commit 4b89ad6403)
yatinkarel
6a5aa9b83c