kube-vip manifest generation failure due to invalid default kube_vip_cidr value

[condaatje]

What happened?

kube-vip manifest generation fails due to invalid default kube_vip_cidr value

Summary

Default value kube_vip_cidr: 32 in roles/kubernetes/node/defaults/main.yml causes invalid YAML in generated kube-vip manifests, preventing kube-vip pods from starting.

Environment

• Kubespray: v2.26.0 (tag: v3.13.11)
• Kubernetes: v1.34.3
• kube-vip: 0.8.0

Bug

File: roles/kubernetes/node/defaults/main.yml (line 72)

kube_vip_cidr: 32

Generated manifest (/etc/kubernetes/manifests/kube-vip.yml):

# Line 23 - INVALID YAML:
    - name: vip_subnet      value: "32"

Error:

couldn't parse as pod(yaml: line 23: mapping values are not allowed in this context)

Expected Output

    - name: vip_subnet
      value: "32"

Root Cause

The Jinja2 template renders the YAML incorrectly when kube_vip_cidr is set to a bare number instead of null/undefined.

Fix

Remove or set to null in roles/kubernetes/node/defaults/main.yml:

kube_vip_cidr:  # unset, or
kube_vip_cidr: null

kube_vip_cidr is optional - kube-vip auto-detects subnet from interface when unset.

Workaround

Set explicitly in inventory:

kube_vip_cidr: null

Impact

• Breaks control plane HA completely
• kube-vip pods fail to start
• VIP not configured
• Affects all clusters using kube-vip with default settings

What did you expect to happen?

Expected Output

    - name: vip_subnet
      value: "32"

How can we reproduce it (as minimally and precisely as possible)?

run cluster.yml for HA cluster using kube_vip setup like this: https://docs.nvidia.com/networking/display/kubernetes2310/deployment/kubespray.html#customize-installation

OS

Ubuntu 24

Version of Ansible

ansible [core 2.17.14]

Version of Python

Python 3.13.11

Version of Kubespray (commit)

20ab917

Network plugin used

cilium

Full inventory with variables

n/a

Command used to invoke ansible

cluster.yml

Output of ansible run

n/a

Anything else we need to know

No response

[tico88612]

I think #12835 already fixed that.

I will close #12838