Bash script for Proxmox network diagnostics. Here are the key features:

1. Interactive Menu System:
   - Main menu with multiple diagnostic options
   - Sub-menus for detailed testing of specific components
   - Clear color-coded output for better readability

2. Major Functions:
   - DNS resolution testing
   - Port testing (specific or common Proxmox ports)
   - Network interface inspection
   - Connectivity testing (ping, MTR, bandwidth)
   - Network card diagnostics
   - Firewall status checking

3. Additional Features:
   - Root privilege check
   - Automatic installation of required tools if missing
   - Color-coded output for better visibility
   - Error handling for various scenarios
   - Support for both automated and interactive testing

To use the script:

1. Save it to a file (e.g., `proxmox_network_diagnostic.sh`)
2. Make it executable: `chmod +x proxmox_network_diagnostic.sh`
3. Run it as root: `sudo ./proxmox_network_diagnostic.sh`