Azure Virtual Desktop Connectivity Test Script

PowerShell script for diagnosing Azure Virtual Desktop (AVD) connectivity issues and disconnects from end-user devices. Performs extensive network testing without requiring Azure credentials.

Features

🔍 Network Interface Detection

• Identifies active connection type (Wi-Fi, Ethernet, VPN)
• Displays link speed, IP/MAC addresses
• Shows Wi-Fi SSID and signal strength
• Warns about power management settings that cause disconnects
• Detects problematic configurations

🌐 Comprehensive Connectivity Testing

Tests 9 Azure Virtual Desktop endpoints:

• rdgateway-r0.wvd.microsoft.com
• rdgateway-r1.wvd.microsoft.com
• rdgateway-g-us-r0.wvd.microsoft.com
• rdgateway-g-us-r1.wvd.microsoft.com
• rdbroker.wvd.microsoft.com
• rdweb.wvd.microsoft.com
• rdgateway.wvd.microsoft.com (redirect server)
• licensing.rd.microsoft.com (RDP licensing)
• diagnostics.wvd.microsoft.com (diagnostics)

Per-endpoint tests:

• DNS resolution
• TCP port 443 connectivity
• HTTPS endpoint response
• Network latency (ping time)
• Packet loss (20 packet test)
• Network jitter (latency variance)
• Connection stability (detects resets/timeouts)
• MTU size (fragmentation detection)

🚨 Advanced Disconnect Diagnostics

• Azure AD Authentication Tests - Verifies login.microsoftonline.com, graph.microsoft.com, auth.gfx.ms connectivity
• WebSocket Connectivity - Tests RDP Web Client support and protocol upgrade capability
• DNS Resolution Consistency - Detects split-DNS, round-robin, and DNS consistency issues
• TCP Reset Statistics - Analyzes connection resets, TIME_WAIT states, and system event logs
• UDP Connectivity - Tests ports 3478, 3479, 3390 for RDP Shortpath
• Time Synchronization - Detects clock drift causing auth failures
• DNS Cache & TTL - Identifies stale DNS issues
• Connection Broker Stress Test - Tests broker stability under load
• Background Network Activity - Detects bandwidth-heavy applications
• Network Adapter Power Management - Identifies sleep settings causing disconnects
• IPv4 vs IPv6 Testing - Compares protocol performance
• Sustained Connection Test - 30 seconds of continuous monitoring to catch intermittent drops

📊 Reporting & Analysis

• Color-coded console output (Green/Yellow/Red)
• Detailed log files - One timestamped log per test run
• CSV export - Daily summary file for trending in Excel
• Success rate calculations
• Actionable recommendations for identified issues

Requirements

Important

PowerShell 7.0 or later is required - PowerShell 5.1 is NOT supported

• Windows 10/11 or Windows Server
• Internet connectivity
• Administrator privileges recommended (for full diagnostics)

Installing PowerShell 7

This script requires PowerShell 7 for improved performance and reliability.

Option 1: Using Windows Package Manager (Recommended)

winget install Microsoft.PowerShell

Option 2: Direct Download

Download and install from: https://aka.ms/powershell

Verify Installation

pwsh -Version

You should see version 7.0 or higher.

Installation

Option 1: Download Just the Script (Easiest)

1. Go to Test-AVDEndUserConnectivity.ps1
2. Click the "Raw" button (top right)
3. Right-click → "Save As..." → Save to your desired location
4. Or use PowerShell to download directly:

Invoke-WebRequest -Uri "https://raw.githubusercontent.com/colinweiner111/AVD-Connectivity-Test/master/Test-AVDEndUserConnectivity.ps1" -OutFile "Test-AVDEndUserConnectivity.ps1"

5. Run with PowerShell 7:

pwsh .\Test-AVDEndUserConnectivity.ps1

Option 2: Download All Files as ZIP

1. Go to https://github.com/colinweiner111/AVD-Connectivity-Test
2. Click the green "Code" button
3. Select "Download ZIP"
4. Extract the ZIP file to your desired location

Option 3: Clone with Git (If Git is Installed)

git clone https://github.com/colinweiner111/AVD-Connectivity-Test.git
cd AVD-Connectivity-Test

Unblock the Script

After downloading, unblock the script to allow execution:

Unblock-File -Path .\Test-AVDEndUserConnectivity.ps1

Usage

Basic Usage

Run with default settings (tests every 5 minutes):

pwsh .\Test-AVDEndUserConnectivity.ps1

Custom Test Interval

Test every 3 minutes:

pwsh .\Test-AVDEndUserConnectivity.ps1 -IntervalMinutes 3

Custom Log Location

Save logs to a specific directory:

pwsh .\Test-AVDEndUserConnectivity.ps1 -LogPath "C:\AVD-Logs"

Combined Parameters

.\Test-AVDEndUserConnectivity.ps1 -IntervalMinutes 10 -LogPath "C:\Logs"

Stop the Script

Press Ctrl+C to stop monitoring

Output Files

Log Files

• Format: AVD-Connectivity-YYYYMMDD-HHMMSS.log
• Location: Script directory or custom -LogPath
• Content: Detailed timestamped test results
• Example: AVD-Connectivity-20251124-143022.log

CSV Summary Files

• Format: AVD-Connectivity-Summary-YYYYMMDD.csv
• Location: Same as log files
• Content: Aggregated metrics for trending analysis
• Updates: Appends new row after each test run

CSV Columns Include:

• Timestamp
• Overall success rates
• Per-endpoint DNS/TCP/HTTPS status
• Latency, packet loss, jitter metrics
• Connection stability percentages

Import into Excel to:

• Create charts showing performance over time
• Identify patterns (e.g., disconnects at specific times)
• Compare Wi-Fi vs Ethernet performance
• Present evidence to network teams

Parameters

Parameter	Type	Default	Description
IntervalMinutes	Integer	5	Time in minutes between each connectivity test
LogPath	String	Script directory	Path where log files will be saved

Common Issues Detected

⚠️ Network Adapter Power Management

Symptom: Random disconnects after periods of inactivity
Detection: Script warns if "Allow computer to turn off device to save power" is enabled
Fix: Disable power management in adapter properties

⚠️ Wi-Fi Performance

Symptom: Higher latency and jitter compared to Ethernet
Detection: Script identifies connection type and signal strength
Fix: Switch to Ethernet or improve Wi-Fi signal

⚠️ UDP Blocked

Symptom: Poor video/audio quality, high latency
Detection: UDP ports 3478-3479 unreachable
Fix: Open UDP ports in firewall for RDP Shortpath

⚠️ Time Synchronization Issues

Symptom: Authentication failures, session drops
Detection: Clock drift exceeds acceptable threshold
Fix: Enable and restart Windows Time service

⚠️ High Packet Loss

Symptom: Choppy experience, frequent disconnects
Detection: Packet loss percentage >5%
Fix: Check network hardware, ISP connection quality

⚠️ IPv6 Performance Issues

Symptom: Slow connection establishment, delays
Detection: IPv6 latency significantly higher than IPv4
Fix: Disable IPv6 or fix IPv6 routing

Understanding Results

Success Rates

• 100% - All tests passed (optimal)
• 90-99% - Minor issues detected
• 70-89% - Significant issues present
• <70% - Severe connectivity problems

Latency Ratings

• <50ms - Excellent
• 50-100ms - Good
• 100-200ms - Fair
• >200ms - Poor (may cause disconnect issues)

Packet Loss

• 0% - Optimal
• <5% - Minimal (acceptable)
• 5-15% - Moderate (may cause issues)
• >15% - High (will cause disconnects)

Jitter

• <5ms - Excellent
• 5-15ms - Acceptable
• 15-30ms - Moderate
• >30ms - High (causes quality issues)

Troubleshooting

Script Won't Run

Error: "Execution of scripts is disabled on this system"

Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser

Missing Permissions

Some tests require administrator privileges. Run PowerShell as Administrator for complete diagnostics.

Firewall Blocks

If your organization blocks PowerShell scripts, work with IT to whitelist this script or run in approved environment.

Contributing

Contributions are welcome! Please feel free to submit issues or pull requests.

Areas for Enhancement

• Email/webhook alerting on failures
• Baseline comparison (alert on deviation)
• Additional cloud environments (GCC High, DoD)
• Session host testing (for VPN-connected users)

License

This project is licensed under the MIT License - see the LICENSE file for details.

Author

Created for diagnosing Azure Virtual Desktop connectivity issues in enterprise environments.

Changelog

Version 1.0.0 (2025-11-24)

• Initial release
• Complete AVD gateway testing suite
• Advanced disconnect diagnostics
• CSV export for trending
• Network interface detection
• Power management checks
• IPv6 testing
• Sustained connection monitoring

Support

For issues, questions, or feature requests, please open an issue on GitHub.

Acknowledgments

• Microsoft Azure Virtual Desktop documentation
• PowerShell community for networking cmdlets
• Network troubleshooting best practices

Microsoft Documentation Resources

Azure Virtual Desktop

• AVD Overview and Architecture
• Network Connectivity Requirements
• RDP Shortpath for Public Networks
• Required URLs and Endpoints

Troubleshooting Guides

• Troubleshoot Connections to Azure Virtual Desktop
• Diagnose Graphics Performance Issues
• Azure Virtual Desktop Insights

Network Requirements

• Bandwidth Recommendations
• Proxy Server Support
• Azure Virtual Desktop Experience Estimator

How Azure Virtual Desktop Connectivity Works

┌─────────────────┐
│   End User      │
│   Device        │ ← This script tests from here
└────────┬────────┘
         │ Internet Connection
         │ (Wi-Fi/Ethernet/VPN)
         │
         ▼
┌─────────────────────────────────────────────┐
│   Azure Virtual Desktop Gateway             │
│   - rdgateway.wvd.microsoft.com            │
│   - rdbroker.wvd.microsoft.com             │
│   - rdweb.wvd.microsoft.com                │
│                                             │
│   Public Endpoints                          │
│   - Port 443 (HTTPS/Gateway)               │
│   - Ports 3478/3479 (STUN/TURN)            │
│   - Port 3390 (UDP RDP Shortpath)          │
└────────┬────────────────────────────────────┘
         │ Azure Backbone Network
         │ (Private/Optimized)
         │
         ▼
┌─────────────────────────────────────────────┐
│   Session Hosts (Private VNet)             │
│   - Windows 10/11 Multi-session            │
│   - Windows Server                          │
│   - Private IP Addresses                    │
└─────────────────────────────────────────────┘

Test Coverage:
✓ User Device → Gateway (All tests)
✗ Gateway → Session Host (Managed by Azure)

Connection Flow

1. User initiates connection → Contacts AVD Gateway
2. Authentication → Azure AD validates user
3. Broker assignment → Determines which session host to use
4. Gateway establishes tunnel → Connects to session host
5. RDP session begins → User sees their desktop

Where Disconnects Typically Occur

• 🔴 User's Internet Connection (Most Common) - Poor Wi-Fi, ISP issues
• 🔴 Network Adapter Power Management - Device goes to sleep
• 🔴 UDP Blocked - Forces TCP fallback (slower, less stable)
• 🟡 High Latency/Jitter - Network congestion
• 🟡 DNS Issues - Stale cache, slow resolution
• 🟢 Azure Gateway/Session Host (Rare) - Azure manages reliability

This script focuses on identifying issues in the user-controllable areas (red/yellow zones).

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Note: This script is for diagnostic purposes only and does not modify any system settings without user intervention.