bug: ansible_default_ipv4 fact & IPv6 only machine

[nicostrebel]

Summary

Inside /templates/keepalived.conf.j2 the Ansible fact "ansible_default_ipv4" is used three times.
If you want to run an IPv6 / Hybrid cluster which has an IPv6 main-address you will run in either of those two problems:

When no IPv4 interface is configured:
The execution fails with a fatal error and Ansible will stop the provisioning.

When both IPv4 and IPv6 interfaces are configured:
It will setup the keepalived VRRP on the wrong interface.

I for myself have just changed all occurrence of "ansible_default_ipv4" to "ansible_default_ipv6" for a workaround.

If it is possible it would be nice if you can integrate a check which evaluates if provided node ip/s are IPv4 or IPv6 and then based on the check later call the corresponding Ansible fact. An even easier workaround would be to use a role variable to enable IPv6.

Issue Type

Bug Report

Ansible Version

ansible [core 2.14.2]
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/anon/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.10/site-packages/ansible
  ansible collection location = /home/anon/.ansible/collections:/usr/share/ansible/collections
  executable location = /usr/bin/ansible
  python version = 3.10.9 (main, Dec 19 2022, 17:35:49) [GCC 12.2.0] (/usr/bin/python)
  jinja version = 3.1.2
  libyaml = True

Steps to Reproduce

Inventory:
[masters]
rancher-server01 ansible_host=[IPv6-Address] rke2_type=server
rancher-server02 ansible_host=[IPv6-Address] rke2_type=server
rancher-server03 ansible_host=[IPv6-Address] rke2_type=server

[workers]
rancher-node01 ansible_host=[IPv6-Address] rke2_type=agent
rancher-node02 ansible_host=[IPv6-Address] rke2_type=agent
rancher-node03 ansible_host=[IPv6-Address] rke2_type=agent

[k8s_cluster:children]
masters
workers

Playbook:

• name: Deploy RKE2
  hosts: all
  become: yes
  become_user: root
  become_method: su
  vars:
  rke2_ha_mode: true
  rke2_api_ip : [IPv6-Address]
  rke2_server_options:
  - "cluster-cidr: 2001:cafe:42:0::/56"
  - "service-cidr: 2001:cafe:42:1::/112"
  rke2_custom_registry_mirrors:
  - name: docker.io
  endpoint:
  - "https://registry.ipv6.docker.com"
  roles:
  • role: lablabs.rke2

Expected Results

Provisioning will run through all steps as usual and will bind keepalived VRRP on IPv6 Interface.

Actual Results

Provisioning fails at keepalived VRRP if no IPv4 is setup or will use wrong interface in an IPv4/IPv6 hybrid setup.