net: adapt role to deal with cloud-init/netplan

roles/net/README

@@ -0,0 +1,28 @@
+# Net role
+
+(Re-)configures host networking using ifupdown, uptionally renaming interfaces
+based on MAC address.
+
+Note: this role disables cloud-init handling of network configuration.
+
+See /usr/share/doc/udev/README.Debian.gz for details on how interface renaming
+is handled.
+
+## Troubleshooting
+
+As distributions adopt "modern" automatic configuration tools things might
+break, in particular udev rules tend to get clobbered.
+
+These commands can help debug why the changes are not being applied:
+
+```
+SYSTEMD_LOG_LEVEL=debug \
+  udevadm test-builtin net_setup_link /sys/class/net/<iface>
+```
+
+```
+SYSTEMD_LOG_LEVEL=debug \
+  udevadm test -a add /sys/class/net/<iface>
+```
+
+Note: the `udevadm test` command seems to apply changes and not just test.

roles/net/handlers/main.yaml

@@ -1,20 +1,20 @@
 # vim:ts=2:sw=2:et:ai:sts=2
 ---
-- name: _tina_restart_udev
-  ansible.builtin.service:
-    name: udev
-    state: restarted
-  listen: _tina_restart_net_all
-
 - name: _tina_reconfigure_network
   ansible.builtin.shell:  # noqa: risky-shell-pipe
     cmd: >-
-      ifdown --all --force;
-      for dev in `ip -o link show | sed -n 's/[0-9]*: \(\S\+\):.*/\1/p'`; do
+      networkctl reload;
+      ifdown --verbose --all --force;
+      for dev in `ls /sys/class/net`; do
         ip link set dev $dev down;
       done;
-      udevadm trigger -c add -s net;
+      udevadm control --reload;
+      udevadm trigger --action add --subsystem-match net;
       ip addr flush scope global;
-      ifup --all --force;
-  listen: _tina_restart_net_all
+      ifup --verbose --all --force;
+  changed_when: true
+
+- name: _tina_update_initramfs
+  ansible.builtin.command:
+    cmd: update-initramfs -u -k all
   changed_when: true

roles/net/tasks/main.yaml

@@ -1,37 +1,63 @@
 # vim:ts=2:sw=2:et:ai:sts=2
 ---
 
+- name: Check cloud-init presence
+  ansible.builtin.stat:
+    path: /etc/cloud/cloud.cfg
+  register: _cloud_init_cfg
+  check_mode: false
+
+- name: Disable cloud-init network configuration
+  ansible.builtin.copy:
+    dest: /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg
+    mode: '0644'
+    content: |
+      network: {config: disabled}
+  when: _cloud_init_cfg.stat.exists
+
+- name: Find cloud-init generated netplan configuration files
+  ansible.builtin.find:
+    paths:
+      - /etc/netplan
+    patterns:
+      - ??-cloud-init.yaml
+  register: _netplan_cfg
+  when: _cloud_init_cfg.stat.exists
+
+- name: Find netplan generated configuration files
+  ansible.builtin.find:
+    paths:
+      - /run/systemd/network
+      - /run/udev/rules.d
+    patterns:
+      - ??-netplan-*.link
+      - ??-netplan-*.network
+      - ??-netplan-*.rules
+  register: _networkd_cfg
+  when: _cloud_init_cfg.stat.exists
+
+- name: Remove generated configuration files
+  ansible.builtin.file:
+    path: '{{ item.path }}'
+    state: absent
+  loop: '{{ _networkd_cfg.files + _netplan_cfg.files }}'
+  when: _cloud_init_cfg.stat.exists
+
 - name: Ensure ifupdown is present
-  ansible.builtin.apt:
+  ansible.builtin.package:
     name: ifupdown
     state: present
 
-- name: Gather facts about services
-  ansible.builtin.service_facts:
-  # Run normally even in check mode.
-  check_mode: false
-  when: ansible_service_mgr == 'systemd'
-
-- name: Stop and disable conflicting services
-  ansible.builtin.service:
-    name: '{{ item }}'
-    state: stopped
-    enabled: false
-    masked: true
-  when: ansible_service_mgr == 'systemd' and item in services
-  with_items:
-    - systemd-network-generator.service
-    - systemd-networkd.service
-  notify: _tina_reconfigure_network
-
 - name: Create udev persistent rules
   ansible.builtin.template:
     src: 70-persistent-net.rules.j2
     dest: /etc/udev/rules.d/70-persistent-net.rules
     owner: root
     group: root
     mode: '0644'
-  notify: _tina_restart_net_all
+  notify:
+    - _tina_reconfigure_network
+    - _tina_update_initramfs
   when: net__use_udev_persistent_rules | bool
 
 - name: Configure interfaces
@@ -41,7 +67,8 @@
     owner: root
     group: root
     mode: '0644'
-  notify: _tina_reconfigure_network
+  notify:
+    - _tina_reconfigure_network
   when: net__interfaces
 
 - name: Apply configuration