cloud-init fails to configure network interfaces running with OpenStack cloud

This bug was originally filed in Launchpad as [LP: #1857031](https://bugs.launchpad.net/cloud-init/+bug/1857031)

Launchpad details

affected_projects = ['nova']

assignee = madhuri-rai07

assignee_name = Madhuri Kumari

date_closed = None

date_created = 2019-12-19T16:47:02.075713+00:00

date_fix_committed = 2019-12-19T17:42:35.350378+00:00

date_fix_released = 2019-12-19T17:42:35.350378+00:00

id = 1857031

importance = undecided

is_complete = False

lp_url = https://bugs.launchpad.net/cloud-init/+bug/1857031

milestone = None

owner = madhuri-rai07

owner_name = Madhuri Kumari

private = False

status = incomplete

submitter = madhuri-rai07

submitter_name = Madhuri Kumari

tags = []

duplicates = []

_Launchpad user **Madhuri Kumari(madhuri-rai07)** wrote on 2019-12-19T16:47:02.075713+00:00_

cloud-init 18.5:

Node has 3 interfaces:
 -enp5s0f0 - not connected
 -enp5s0f1 - connected
 -ib0 - an HFI port

Centos7.6 running on the node.

Openstack boots the server with two interfaces enp5s0f1 and ib0 and it is successful but the node is not reachable. On the node, the cloud-init configures the wrong interface enp5s0f0. It is because cloud-init fails to configure network interfaces running with OpenStack cloud if any of the network interfaces don't exist on the node. In this case, ib0 was missing.

Please note that when I try to boot the server with only 1 interface enp5s0f1, everything works fine and the node is reachable too.

Logs: http://paste.openstack.org/show/787707/
network-data and nics: http://paste.openstack.org/show/787797/ (note that enp5s0f1 is manually configured)