Fix seed VM interface ordering

Currently the ordering of network interfaces in the seed VM is
non-deterministic. This happens because we apply the 'unique' filter to
the network_interfaces list, which does not guarantee a deterministic
ordering. This list is then transformed and passed to the
stackhpc.libvirt-vm role.

There are two consequences of this:

* it is not possible to determine which interface names should be used
  prior to creating a seed VM
* if a seed VM is recreated, the interface ordering may change

This change fixes the issue by sorting the network_interfaces list
alphabetically before it is transformed and passed to the
stackhpc.libvirt-vm.

A new 'seed_vm_interfaces' variable is also added, which allows for
customisation of the VM's interfaces - potentially allowing for more
complex setups such as trunked VLANs.

Story: 2007259
Task: 38621

There is a second issue, which is that if the seed VM has a
network interface not configured with a gateway, cloud-init will fail to
configure the network interfaces on the host. This has been observed on
CentOS 8, but is probably more tied to the version of cloud-init, and
may affect CentOS 7. The following error is seen in the cloud-init logs:

    KeyError: 'gateway'

This change has been addressed in the jriguera.configdrive role, and
this change updates the version used in requirements.yml.

Story: 2007769
Task: 39993

Change-Id: Ib6ab41a3ba320a1fe15d0d23561fad2fab7861e6

ansible/group_vars/all/seed-vm

@@ -48,3 +48,6 @@ seed_vm_data_capacity: 100G
 
 # Format of the seed VM data volume.
 seed_vm_data_format: qcow2
+
+# List of network interfaces to attach to the seed VM.
+seed_vm_interfaces: "{{ network_interfaces | sort | map('net_libvirt_vm_network') | list }}"

ansible/seed-vm-provision.yml

@@ -29,29 +29,6 @@
         group: "{{ ansible_user_gid }}"
       become: True
 
-    - name: Create a temporary user data file locally
-      tempfile:
-        state: file
-      register: seed_user_data_file
-      delegate_to: localhost
-
-    # The user data script is used to bring up the network interfaces that will
-    # be configured by metadata in the configdrive. For some reason resolv.conf
-    # gets configured with 660 permissions, so fix that here also.
-    - name: Ensure the user data file exists
-      copy:
-        content: |
-          #!/bin/bash
-          {% for interface in hostvars[seed_host].network_interfaces | map('net_interface', seed_host) %}
-          # Bounce {{ interface }}.
-          ifdown {{ interface }}
-          ifup {{ interface }}
-          {% endfor %}
-          # Fix permissions of resolv.conf.
-          chmod 644 /etc/resolv.conf
-        dest: "{{ seed_user_data_file.path }}"
-      delegate_to: localhost
-
   roles:
     - role: jriguera.configdrive
       # For now assume the VM OS family is the same as the hypervisor's.
@@ -71,7 +48,6 @@
         {{ hostvars[seed_host].network_interfaces |
            map('net_configdrive_network_device', seed_host) |
            list }}
-      configdrive_config_user_data_path: "{{ seed_user_data_file.path }}"
 
   tasks:
     - name: Set a fact containing the configdrive image path
@@ -91,14 +67,6 @@
       with_items:
         - "{{ image_cache_path }}/{{ seed_host | to_uuid }}.gz"
 
-    - name: Ensure unnecessary local files are removed
-      file:
-        path: "{{ item }}"
-        state: absent
-      with_items:
-        - "{{ seed_user_data_file.path }}"
-      delegate_to: localhost
-
 - name: Ensure that the seed VM is provisioned
   hosts: seed-hypervisor
   vars:
@@ -128,8 +96,7 @@
           memory_mb: "{{ hostvars[seed_host].seed_vm_memory_mb }}"
           vcpus: "{{ hostvars[seed_host].seed_vm_vcpus }}"
           volumes: "{{ hostvars[seed_host].seed_vm_volumes + [seed_vm_configdrive_volume] }}"
-          interfaces: >
+          interfaces: "{{ hostvars[seed_host].seed_vm_interfaces }}"
-            {{ hostvars[seed_host].network_interfaces | map('net_libvirt_vm_network') | list }}
           console_log_enabled: true
       become: True
 

etc/kayobe/seed-vm.yml

@@ -33,6 +33,22 @@
 # Format of the seed VM data volume.
 #seed_vm_data_format:
 
+# List of network interfaces to attach to the seed VM. Format is as accepted by
+# the stackhpc.libvirt-vm role's libvirt_vms.interfaces variable. Default is
+# one interface for each network in 'network_interfaces'.
+#
+# Example with one interface connected to a libvirt network called
+# 'libvirt-net', and another interface directly plugged into a host device
+# called 'eth1':
+#
+# seed_vm_interfaces:
+#   - network: libvirt-net
+#   - type: direct
+#     source:
+#       dev: eth1
+#
+#seed_vm_interfaces:
+
 ###############################################################################
 # Dummy variable to allow Ansible to accept this file.
 workaround_ansible_issue_8743: yes

releasenotes/notes/fix-seed-multiple-networks-458915b085a9478c.yaml

@@ -0,0 +1,19 @@
+---
+fixes:
+  - |
+    Fixes an issue with seed VMs with multiple network interfaces where
+    interfaces could come up in a different order if the VM is recreated. The
+    interfaces are now created in alphabetical order of their Kayobe network
+    name by default. See `story 2007259
+    <https://storyboard.openstack.org/#!/story/2007259>`__ for details.
+features:
+  - |
+    Adds a ``seed_vm_interfaces`` variable which defines the network interfaces
+    to which the seed VM is attached.
+upgrade:
+  - |
+    The default order of network interfaces in the seed VM is now sorted
+    alphabetically based on their Kayobe network name. This may require the
+    seed's network interface names to be changed in configuration if the seed
+    VM is recreated.  See `story 2007259
+    <https://storyboard.openstack.org/#!/story/2007259>`__ for details.

requirements.yml

@@ -3,7 +3,7 @@
   version: 1.3.1
 - src: jriguera.configdrive
   # There are no versioned releases of this role.
-  version: a5c3c19d0cda7b6960c9200a30b5dbe73d2eef96
+  version: 56daf0017783bd4fa5722da4ee91b66ddd4e6b6a
 - src: MichaelRigart.interfaces
   version: v1.5.0
 - src: mrlesmithjr.manage-lvm