# Implementation Plan

- [ ] 1. Create role directory structure and basic configuration
  - Create the fastpass-additional-control-plane role directory structure
  - Set up defaults/main.yml with required variables and firewall services
  - Create meta/main.yml with role metadata and dependencies
  - _Requirements: 2.1, 2.2, 2.4_

- [ ] 2. Implement join token and certificate key retrieval
  - [ ] 2.1 Create tasks to generate new join tokens from first control plane
    - Write Ansible tasks to execute kubeadm token create on first control plane node
    - Implement token validation and expiration checking
    - Add error handling for token generation failures
    - _Requirements: 1.4, 5.4_

  - [ ] 2.2 Implement certificate key retrieval and management
    - Create tasks to upload and retrieve certificate keys from first control plane
    - Add certificate key expiration handling and rotation
    - Implement secure handling of certificate keys in variables
    - _Requirements: 1.4, 5.1_

  - [ ] 2.3 Create discovery token CA certificate hash retrieval
    - Write tasks to extract CA certificate hash from first control plane
    - Implement validation of certificate hash format
    - Add error handling for certificate retrieval failures
    - _Requirements: 1.4, 5.4_

- [ ] 3. Implement DNS configuration and firewall setup
  - [ ] 3.1 Configure DNS records for additional control plane nodes
    - Integrate dns-manager role for consistent DNS record creation
    - Pass appropriate host_name variable to dns-manager
    - Add DNS propagation wait and validation
    - _Requirements: 3.1, 3.2, 3.4_

  - [ ] 3.2 Set up firewall rules for control plane services
    - Reuse kubernetes_services_control_plane from defaults
    - Implement UFW firewall rule creation for Debian/Ubuntu systems
    - Add conditional logic for different operating systems
    - _Requirements: 1.2, 2.4_

- [ ] 4. Implement kubelet configuration and cluster join
  - [ ] 4.1 Create initial kubelet configuration
    - Write kubelet config.yaml with systemd cgroup driver
    - Set containerd socket endpoint configuration
    - Ensure proper file permissions and ownership
    - _Requirements: 1.3, 2.3_

  - [ ] 4.2 Execute kubeadm join for control plane
    - Implement kubeadm join command with control-plane flag
    - Use retrieved join token, certificate key, and CA cert hash
    - Add proper command argument construction and validation
    - Include idempotency checks to prevent duplicate joins
    - _Requirements: 1.1, 1.4, 5.1, 5.2_

  - [ ] 4.3 Ensure kubelet service management
    - Enable and start kubelet systemd service
    - Add service status validation and error handling
    - Implement service restart logic if needed
    - _Requirements: 1.3, 1.5_

- [ ] 5. Implement kubeconfig management and validation
  - [ ] 5.1 Configure kubeconfig for additional control plane nodes
    - Integrate kubeconfig-manager role for consistent configuration
    - Pass cluster_name variable to kubeconfig-manager
    - Ensure proper kubeconfig merging with existing configurations
    - _Requirements: 4.1, 4.2, 4.3_

  - [ ] 5.2 Implement cluster join validation
    - Create tasks to verify node successfully joined as control plane
    - Add kubectl commands to check node status and roles
    - Implement cluster health validation checks
    - _Requirements: 1.5, 4.4_

- [ ] 6. Add comprehensive error handling and idempotency
  - [ ] 6.1 Implement pre-flight validation checks
    - Check if node is already joined to cluster
    - Validate required variables are defined
    - Verify first control plane node accessibility
    - Add system resource and prerequisite checks
    - _Requirements: 5.1, 5.2, 5.4, 5.5_

  - [ ] 6.2 Add retry logic and failure recovery
    - Implement retry mechanisms for transient failures
    - Add exponential backoff for network-related operations
    - Create cleanup tasks for partial join failures
    - _Requirements: 5.3, 5.4_

- [ ] 7. Integration with FastPass deployment workflow
  - [ ] 7.1 Ensure compatibility with deploy-fastpass-4step.yml
    - Verify role works with fastpass_control_plane[1:] host group
    - Test integration with existing playbook structure
    - Validate dependency on first control plane completion
    - _Requirements: 6.1, 6.2, 6.3, 6.4_

  - [ ] 7.2 Add proper task documentation and metadata
    - Include role header with author, version, and description
    - Add inline comments for complex task logic
    - Document required variables and their purposes
    - _Requirements: 2.2, 2.5_

- [ ]* 8. Create comprehensive testing and validation
  - [ ]* 8.1 Write unit tests for individual tasks
    - Create test cases for token retrieval logic
    - Test kubeadm join command construction
    - Validate error handling scenarios
    - _Requirements: 1.1, 1.4, 5.1_

  - [ ]* 8.2 Implement integration tests
    - Test multi-node control plane deployment
    - Validate cluster health after additional nodes join
    - Test failover scenarios and cluster resilience
    - _Requirements: 1.5, 6.5_

  - [ ]* 8.3 Add validation scripts and health checks
    - Create scripts to verify cluster state after deployment
    - Implement automated health validation
    - Add performance and resource usage monitoring
    - _Requirements: 1.5, 4.4_