heat/releasenotes/notes/os-neutron-net-segments-attribute-semi-predictable-b40a869317d053cc.yaml
Harald Jensås 539b2a4c49 Net attr: Sort segments without name attribute first
Useing get_attr, pulling index 0 in the segments list
of a network to associate the a subnet with the "first"
segment is useful since the "first" segment is created
by neutron behind the scenes on network create. A resource
reference cannot be used since the "first" segment is'nt
a heat resource.

The issue is the order of the segments list is'nt reliable.

On stack update index 0 may be a different segment, and
we end up trying to update the segment_id for a subnet.
Changeing the segment association is not allowed, so
the stack update fails.

While not perfect, sorting the list so that segments where
name is None comes first will ensure that index 0 can be used.

The template author should ensure segments defined in the heat
template all have a names set, so that only the segment creted
implicitly by neutron have 'None' name.

Closes-Bug: #1894920
Change-Id: I097aba2a97144327bec188e6c71629d0f6c95901
2020-09-18 14:03:33 +00:00

17 lines
816 B
YAML

---
fixes:
- |
The ordering in the list of segments returned by ``OS::Neutron::Net``
resources is not predictable. Stack updates changeing attributes
of the network can cause the list of segments to shift.
The ordering is now slightly more predictable, segments with name=``None``
are now placed first in the list. This doesn't guarantee the order, but
typically only the segment implicitly created by neutron has no name
attribute set. The template author should ensure other segments on the
network does have a name set, so that the implicit segment will always be
index 0. Resolving attributes of the implcitly created segment on the
network resource can then predictibly happen using index 0. See `bug:
1894920 <https://bugs.launchpad.net/tripleo/+bug/1894920>`_.