Server Watcher - SSH Connection Monitor

An Avalonia-based .NET 9 desktop application that monitors SSH connectivity to multiple servers using configured credentials.

Features

• Configure multiple servers with associated credential groups
• Test SSH connectivity to all configured servers
• Individual server retest - Retest button for each server to quickly verify a single connection
• Website monitoring - Optional HTTP/HTTPS endpoint monitoring for each server
• Open in Browser - Quick-launch button to open configured websites in system default browser
• Automatic IP resolution - Displays resolved IP addresses next to hostnames
• Visual status indicators (red/green/orange lights) for each server connection state
• Dual status display: SSH connectivity + website availability
• Real-time connection status updates
• Password encryption tool - Built-in utility to encrypt passwords for secure storage
• Encrypted password support - Automatically decrypts passwords from config file at runtime
• Adjustable font size - Slider control to customize text size (8-24pt, default 12pt)
• Scrollable server list to accommodate any number of servers
• Cross-platform support (Windows, Linux, macOS)

Configuration

The application reads from a serverconfig.json file that must be placed in the same directory as the executable.

Configuration File Format

{
  "Servers": [
    {
      "ServerName": "server1.example.com",
      "Group": "GROUP1",
      "Description": "Production Web Server - Main Application",
      "Path": "/var/www/html",
      "WebSite": "https://server1.example.com"
    },
    {
      "ServerName": "192.168.1.100",
      "Group": "GROUP2",
      "Description": "Database Server - Primary",
      "Path": "/var/lib/mysql"
    },
    {
      "ServerName": "api.example.com",
      "Group": "GROUP1",
      "Description": "API Server",
      "Path": "/opt/api",
      "WebSite": "https://api.example.com:8443/health"
    }
  ],
  "CredentialGroups": [
    {
      "GroupName": "GROUP1",
      "LoginName": "admin",
      "Password": "password123"
    },
    {
      "GroupName": "GROUP2",
      "LoginName": "root",
      "Password": "rootpass"
    }
  ]
}

Configuration Elements

• Servers: List of servers to monitor

  • ServerName: Hostname or IP address of the server (hostnames will show resolved IP in blue)
  • Group: Reference to the credential group to use (e.g., "GROUP1", "GROUP2")
  • Description: Optional descriptive label for the server (displayed in the UI)
  • Path: Optional file system path for file browsing functionality
  • WebSite: Optional HTTP/HTTPS URL to monitor (supports custom ports, e.g., "https://server.com:8443/health")

• CredentialGroups: List of credential sets

  • GroupName: Unique identifier for the credential group
  • LoginName: SSH username
  • Password: SSH password (can be encrypted using the built-in Password Encryption Tool)

Building and Running

Prerequisites

• .NET 9 SDK
• SSH access to test servers (optional, for testing)

Build

dotnet build ServerWatcher/ServerWatcher.csproj

Run

dotnet run --project ServerWatcher/ServerWatcher.csproj

Or navigate to the build output directory and run the executable:

cd ServerWatcher/bin/Debug/net9.0
./ServerWatcher

Publish as Single-File Executable

To create a standalone, self-contained executable that doesn't require .NET runtime to be installed:

Windows

# Run the provided script
publish-windows.bat

# Or manually:
dotnet publish ServerWatcher/ServerWatcher.csproj -c Release -r win-x64 --self-contained true -p:PublishSingleFile=true -p:IncludeNativeLibrariesForSelfExtract=true -p:EnableCompressionInSingleFile=true -o publish/win-x64

Linux

# Make script executable and run
chmod +x publish-linux.sh
./publish-linux.sh

# Or manually:
dotnet publish ServerWatcher/ServerWatcher.csproj -c Release -r linux-x64 --self-contained true -p:PublishSingleFile=true -p:IncludeNativeLibrariesForSelfExtract=true -p:EnableCompressionInSingleFile=true -o publish/linux-x64

macOS

# Make script executable and run
chmod +x publish-macos.sh
./publish-macos.sh

# Or manually:
dotnet publish ServerWatcher/ServerWatcher.csproj -c Release -r osx-x64 --self-contained true -p:PublishSingleFile=true -p:IncludeNativeLibrariesForSelfExtract=true -p:EnableCompressionInSingleFile=true -o publish/osx-x64

The published executable will be in the publish/[platform] directory along with the serverconfig.json file. The configuration file remains separate and can be edited without rebuilding the application.

Usage

Basic Operation

1. Edit the serverconfig.json file with your servers and credentials
2. Launch the application
3. Click the "Test All Connections" button to test SSH connectivity and website availability
4. Use the "Retest" button next to any server to quickly retest just that specific server
5. Adjust font size using the slider control in the top toolbar (8-24pt range, default 12pt)
6. View the status indicators for each server:

SSH Status (First Row)

• Gray: Not tested
• Orange: Connecting
• Green: Successfully connected
• Red: Connection failed

Website Status (Second Row - only shown if WebSite is configured)

• Gray: Not tested or no website configured
• Orange: Checking website
• Green: Website responding (HTTP 200-299)
• Red: Website unreachable or error response
• Open in Browser button: Click to launch the configured website in your system's default web browser
  • This button is only visible for servers that have a website URL configured
  • Opens the exact URL configured in the WebSite field

IP Address Display

• Hostnames automatically display their resolved IP address in blue next to the server name
• Example: server1.example.com (192.168.1.100)
• If the ServerName is already an IP address, no additional IP is shown

Individual Server Retest

Each server in the list has a dedicated "Retest" button that allows you to quickly verify a specific server's connectivity without having to retest all servers:

1. Locate the server you want to retest in the list
2. Click the "Retest" button on the right side of that server's status display
3. The application will:
   • Test the SSH connection for that server only
   • Test the website status if a website is configured
   • Update both status indicators for that server
   • Display progress in the status bar at the bottom

This is particularly useful when:

• Troubleshooting connection issues with a specific server
• Verifying that configuration changes worked for one server
• Quickly checking if a temporarily down server is back online
• Avoiding the wait time of retesting all servers when you only need to verify one

Password Encryption

The application supports encrypted passwords in the configuration file for enhanced security.

Encrypting Passwords

1. Launch the application
2. Click the "Encrypt Password" button in the main window
3. In the Password Encryption Tool dialog:
   • Enter your plain text password
   • Click "Encrypt Password"
   • Copy the encrypted password that appears
4. Paste the encrypted password into the Password field in your serverconfig.json file

Example Configuration with Encrypted Password

{
  "CredentialGroups": [
    {
      "GroupName": "GROUP1",
      "LoginName": "admin",
      "Password": "k8vF2Xq9mP3nR5tY7wZ1aB4cD6eG8hJ0"
    }
  ]
}

The application automatically detects and decrypts encrypted passwords at runtime. Plain text passwords are also supported for backward compatibility.

Security Considerations

The application provides password encryption to protect credentials in the configuration file:

• Encrypted passwords: Use the built-in Password Encryption Tool to encrypt passwords before storing them in the config file
• Secure storage: Store the configuration file in a secure location with restricted file permissions
• Access control: Restrict access to the application executable and configuration file
• SSH keys: For maximum security, consider using SSH key-based authentication instead of passwords
• Encryption key: The encryption key is embedded in the application. For enterprise deployments, consider storing the key in a secure vault (e.g., Azure Key Vault, Windows Credential Manager)

Project Structure

ServerWatcher/
├── Models/
│   ├── AppConfiguration.cs      # Configuration data model
│   ├── ServerConfig.cs          # Server configuration
│   ├── CredentialGroup.cs       # Credential group configuration
│   └── ServerStatus.cs          # Runtime server status (SSH + website status)
├── Services/
│   ├── ConfigurationService.cs  # Configuration file loader
│   ├── SshConnectionService.cs  # SSH connectivity tester
│   └── WebsiteCheckService.cs   # HTTP/HTTPS website checker
├── ViewModels/
│   └── MainWindowViewModel.cs   # Main window logic with DNS resolution
├── Views/
│   └── MainWindow.axaml         # Main window UI with dual status indicators
└── serverconfig.json            # Configuration file

Technologies Used

• .NET 9: Latest .NET framework
• Avalonia UI: Cross-platform UI framework
• SSH.NET: SSH connectivity library
• CommunityToolkit.Mvvm: MVVM helpers and utilities

License

This project is provided as-is for monitoring SSH server connectivity.