claude-home/vm-management/CONTEXT.md

Virtual Machine Management - Technology Context

Overview

Virtual machine management for home lab environments with focus on automated provisioning, infrastructure as code, and security-first configuration. This context covers VM lifecycle management, Proxmox integration, and standardized deployment patterns.

Architecture Patterns

Infrastructure as Code (IaC) Approach

Pattern: Declarative VM configuration with repeatable deployments

# Cloud-init template pattern
#cloud-config
users:
  - name: cal
    groups: [sudo, docker]
    ssh_authorized_keys:
      - ssh-rsa AAAAB3... primary-key
      - ssh-rsa AAAAB3... emergency-key
packages:
  - docker.io
  - docker-compose
runcmd:
  - systemctl enable docker
  - usermod -aG docker cal

Template-Based Deployment Strategy

Pattern: Standardized VM templates with cloud-init automation

• Base Templates: Ubuntu Server with cloud-init support
• Resource Allocation: Standardized sizing (2CPU/4GB/20GB baseline)
• Network Configuration: Predefined VLAN assignments (10.10.0.x internal)
• Security Hardening: SSH keys only, password auth disabled

Provisioning Strategies

Cloud-Init Deployment (Recommended for New VMs)

Purpose: Fully automated VM provisioning from first boot Implementation:

1. Create VM in Proxmox with cloud-init support
2. Apply standardized cloud-init template
3. VM configures itself automatically on first boot
4. No manual intervention required

Benefits:

• Zero-touch deployment
• Consistent configuration
• Security hardening from first boot
• Immediate productivity

Post-Install Scripting (Existing VMs)

Purpose: Standardize existing VM configurations Implementation:

./vm-post-install.sh <vm-ip> [username]
# Automated: updates, SSH keys, Docker, hardening

Use Cases:

• Legacy VM standardization
• Imported VM configuration
• Recovery and remediation
• Incremental improvements

Security Architecture

SSH Key-Based Authentication

Pattern: Dual key deployment for security and redundancy

# Primary access key
~/.ssh/homelab_rsa      # Daily operations

# Emergency access key  
~/.ssh/emergency_homelab_rsa  # Backup/recovery access

Security Controls:

• Password authentication completely disabled
• Root login prohibited
• SSH keys managed centrally
• Automatic key deployment

User Privilege Management

Pattern: Least privilege with sudo elevation

# User configuration
username: cal
groups: [sudo, docker]  # Minimal required groups
shell: /bin/bash
sudo: ALL=(ALL) NOPASSWD:ALL  # Operational convenience

Access Controls:

• Non-root user accounts only
• Sudo required for administrative tasks
• Docker group for container management
• SSH key authentication mandatory

Network Security

Pattern: Network segmentation and access control

• Internal Network: 10.10.0.x/24 for VM communication
• Management Access: SSH (port 22) only
• Service Isolation: Application-specific port exposure
• Firewall Ready: iptables/ufw configuration prepared

Lifecycle Management Patterns

VM Creation Workflow

1. Template Selection: Choose appropriate base image
2. Resource Allocation: Size based on workload requirements
3. Network Assignment: VLAN and IP address planning
4. Cloud-Init Configuration: Apply standardized template
5. Automated Provisioning: Zero-touch deployment
6. Verification: Automated connectivity and configuration tests

Configuration Management

Pattern: Standardized system configuration

# Essential packages
packages: [
  "curl", "wget", "git", "vim", "htop", "unzip",
  "docker.io", "docker-compose-plugin"
]

# System services
runcmd:
  - systemctl enable docker
  - systemctl enable ssh
  - systemctl enable unattended-upgrades

Maintenance Automation

Pattern: Automated updates and maintenance

• Security Updates: Automatic installation enabled
• Package Management: Standardized package selection
• Service Management: Consistent service configuration
• Log Management: Centralized logging ready

Resource Management

Sizing Standards

Pattern: Standardized VM resource allocation

# Basic workload (web services, small databases)
vcpus: 2
memory: 4096  # 4GB
disk: 20      # 20GB

# Medium workload (application servers, medium databases)  
vcpus: 4
memory: 8192  # 8GB
disk: 40      # 40GB

# Heavy workload (transcoding, large databases)
vcpus: 6
memory: 16384 # 16GB
disk: 100     # 100GB

Storage Strategy

Pattern: Application-appropriate storage allocation

• System Disk: OS and applications (20-40GB)
• Data Volumes: Application data (variable)
• Backup Storage: Network-attached for persistence
• Cache Storage: Local fast storage for performance

Network Planning

Pattern: Structured network addressing

# Network segments
management: 10.10.0.x/24    # VM management and SSH access
services: 10.10.1.x/24      # Application services
storage: 10.10.2.x/24       # Storage and backup traffic
dmz: 10.10.10.x/24          # External-facing services

Monitoring and Operations

Health Monitoring

Pattern: Automated system health checks

# Resource monitoring
cpu_usage: <80%
memory_usage: <90%  
disk_usage: <85%
network_connectivity: verified

# Service monitoring
ssh_service: active
docker_service: active
unattended_upgrades: active

Backup Strategies

Pattern: Multi-tier backup approach

• VM Snapshots: Point-in-time recovery (Proxmox)
• Application Data: Specific application backup procedures
• Configuration Backup: Cloud-init templates and scripts
• SSH Keys: Centralized key management backup

Performance Tuning

Pattern: Workload-optimized configuration

# CPU optimization
cpu_type: host        # Performance over compatibility
numa: enabled         # NUMA awareness for multi-socket

# Memory optimization  
ballooning: enabled   # Dynamic memory allocation
hugepages: disabled   # Unless specifically needed

# Storage optimization
cache: writethrough   # Balance performance and safety
io_thread: enabled    # Improve I/O performance

Integration Patterns

Container Platform Integration

Pattern: Docker-ready VM deployment

# Automated Docker setup
- docker.io installation
- docker-compose plugin
- User added to docker group
- Service auto-start enabled
- Container runtime verified

SSH Infrastructure Integration

Pattern: Centralized SSH key management

# Key deployment automation
primary_key: ~/.ssh/homelab_rsa.pub
emergency_key: ~/.ssh/emergency_homelab_rsa.pub
backup_system: automated
rotation_policy: annual

Network Services Integration

Pattern: Ready for service deployment

• Reverse Proxy: Nginx/Traefik ready configuration
• DNS: Local DNS registration prepared
• Certificates: Let's Encrypt integration ready
• Monitoring: Prometheus/Grafana agent ready

Common Implementation Workflows

New VM Deployment

1. Create VM in Proxmox with cloud-init support
2. Configure resources based on workload requirements
3. Apply cloud-init template with standardized configuration
4. Start VM and wait for automated provisioning
5. Verify deployment via SSH key authentication
6. Deploy applications using container or package management

Existing VM Standardization

1. Assess current configuration and identify gaps
2. Run post-install script for automated updates
3. Verify SSH key deployment and password auth disable
4. Test Docker installation and user permissions
5. Update documentation with new configuration
6. Schedule regular maintenance and monitoring

VM Migration and Recovery

1. Create VM snapshot before changes
2. Export VM configuration and cloud-init template
3. Test recovery procedure in staging environment
4. Document recovery steps and verification procedures
5. Implement backup automation for critical VMs

Best Practices

Security Hardening

1. SSH Keys Only: Disable password authentication completely
2. Emergency Access: Deploy backup SSH keys for recovery
3. User Separation: Non-root users with sudo privileges
4. Automatic Updates: Enable security update automation
5. Network Isolation: Use VLANs and firewall rules

Operational Excellence

1. Infrastructure as Code: Use cloud-init for reproducible deployments
2. Standardization: Consistent VM sizing and configuration
3. Automation: Minimize manual configuration steps
4. Documentation: Maintain deployment templates and procedures
5. Testing: Verify deployments before production use

Performance Optimization

1. Resource Right-Sizing: Match resources to workload requirements
2. Storage Strategy: Use appropriate storage tiers
3. Network Optimization: Plan network topology for performance
4. Monitoring: Implement resource usage monitoring
5. Capacity Planning: Plan for growth and scaling

This technology context provides comprehensive guidance for implementing virtual machine management in home lab and production environments using modern IaC principles and security best practices.