homelab/.kiro/specs/fastpass-additional-control-plane/requirements.md

Requirements Document

Introduction

This feature involves creating an Ansible role called fastpass-additional-control-plane that will deploy additional control plane nodes to an existing FastPass Kubernetes cluster. The role will follow the same pattern as the existing fastpass-first-control-plane role but will focus on joining nodes to an already initialized cluster rather than initializing a new cluster. This ensures high availability for the Kubernetes control plane by adding redundant master nodes.

Requirements

Requirement 1

User Story: As a DevOps engineer, I want to deploy additional control plane nodes to my FastPass Kubernetes cluster, so that I can achieve high availability and fault tolerance for the cluster control plane.

Acceptance Criteria

1. WHEN the role is executed on a node THEN the system SHALL join the node to the existing Kubernetes cluster as a control plane node
2. WHEN the role runs THEN the system SHALL configure the necessary firewall rules for control plane services
3. WHEN the role executes THEN the system SHALL ensure the kubelet service is properly configured and running
4. WHEN joining the cluster THEN the system SHALL use the correct join token and certificate key from the first control plane node
5. WHEN the role completes THEN the system SHALL verify the node has successfully joined as a control plane node

Requirement 2

User Story: As a system administrator, I want the additional control plane role to follow the same patterns as the first control plane role, so that the codebase remains consistent and maintainable.

Acceptance Criteria

1. WHEN the role is created THEN the system SHALL follow the same directory structure as fastpass-first-control-plane
2. WHEN the role is implemented THEN the system SHALL use similar variable naming conventions and task organization
3. WHEN the role runs THEN the system SHALL include proper error handling and idempotency checks
4. WHEN the role executes THEN the system SHALL use the same firewall service definitions as the first control plane role
5. WHEN the role is documented THEN the system SHALL include proper metadata headers with author, version, and description

Requirement 3

User Story: As a cluster operator, I want the additional control plane nodes to have proper DNS configuration, so that they can be reached by their cluster names and participate in load balancing.

Acceptance Criteria

1. WHEN the role runs THEN the system SHALL configure DNS records for the additional control plane nodes
2. WHEN DNS is configured THEN the system SHALL use the dns-manager role for consistency
3. WHEN the role executes THEN the system SHALL ensure the node can resolve the cluster endpoint
4. WHEN DNS setup completes THEN the system SHALL verify connectivity to the cluster API endpoint

Requirement 4

User Story: As a DevOps engineer, I want the role to handle kubeconfig management for additional control plane nodes, so that I can manage the cluster from any control plane node.

Acceptance Criteria

1. WHEN the role completes THEN the system SHALL configure kubeconfig for the new control plane node
2. WHEN kubeconfig is set up THEN the system SHALL use the kubeconfig-manager role for consistency
3. WHEN the role runs THEN the system SHALL ensure proper permissions are set on kubeconfig files
4. WHEN kubeconfig is configured THEN the system SHALL verify kubectl access works from the new node

Requirement 5

User Story: As a system administrator, I want the role to be idempotent and handle edge cases, so that I can run it multiple times safely without causing issues.

Acceptance Criteria

1. WHEN the role is run multiple times THEN the system SHALL not attempt to rejoin an already joined node
2. WHEN a node is already part of the cluster THEN the system SHALL skip the join process gracefully
3. WHEN the role encounters errors THEN the system SHALL provide clear error messages and fail gracefully
4. WHEN prerequisites are missing THEN the system SHALL report what needs to be configured first
5. WHEN the role runs THEN the system SHALL validate that required variables are defined

Requirement 6

User Story: As a cluster administrator, I want the role to integrate seamlessly with the existing FastPass deployment workflow, so that it can be used in the 4-step deployment process.

Acceptance Criteria

1. WHEN the role is created THEN the system SHALL be compatible with the deploy-fastpass-4step.yml playbook
2. WHEN the role runs THEN the system SHALL work with the fastpass_control_plane[1:] host group
3. WHEN integrated THEN the system SHALL not interfere with the first control plane initialization
4. WHEN the role executes THEN the system SHALL depend on the first control plane node being ready
5. WHEN deployment completes THEN the system SHALL allow worker nodes to join the cluster successfully