Monitoring Azure VPN Gateway

Monitoring your Azure VPN Gateway is crucial for ensuring reliable and secure connectivity. This section guides you through the essential metrics, logs, and tools available for monitoring your VPN gateway's health and performance.

Key Monitoring Areas

Performance Metrics

Azure Monitor provides a rich set of metrics for your VPN Gateway. These metrics help you understand the performance and health of your gateway connections.

Tunnel P2S Bandwidth: Measures the bandwidth usage for Point-to-Site connections.
Tunnel S2S Bandwidth: Measures the bandwidth usage for Site-to-Site connections.
Tunnel P2S Packets In/Out: Tracks the number of packets sent and received for P2S connections.
Tunnel S2S Packets In/Out: Tracks the number of packets sent and received for S2S connections.
Tunnel P2S Egress/Ingress Bytes: Measures the data transfer in bytes for P2S connections.
Tunnel S2S Egress/Ingress Bytes: Measures the data transfer in bytes for S2S connections.
Gateway P2S Connections: The current number of active Point-to-Site connections.
Gateway S2S Connections: The current number of active Site-to-Site connections.

Diagnostic Logs

Enable diagnostic logs to capture detailed information about your VPN Gateway's operations. These logs are invaluable for troubleshooting and auditing.

TunnelDiagnosticLog: Logs events related to VPN tunnels, such as tunnel establishment, disconnection, and rekeying.
GatewayDiagnosticLog: Logs general gateway events, including configuration changes and status updates.
TunnelConnectionDiagnosticLog: Provides detailed information about individual tunnel connections.

To enable diagnostic logs, navigate to your VPN Gateway resource in the Azure portal, go to Diagnostic settings, and click Add diagnostic setting.

Azure Monitor Alerts

Set up alerts in Azure Monitor to be proactively notified of potential issues. You can create alerts based on specific metric thresholds or log queries.

Tip: Consider setting up alerts for when the number of active connections drops unexpectedly or when bandwidth usage exceeds certain thresholds.

Tools and Techniques

Azure Portal

The Azure portal is your primary interface for monitoring.

Navigate to your VPN Gateway resource.
Click on Monitoring in the left-hand menu to access Metrics, Diagnostic logs, and Alerts.
The Overview page also provides a quick glance at the gateway's status.

Azure CLI

Use Azure CLI commands to retrieve monitoring data programmatically.

# Get VPN gateway metrics
az monitor metrics list --resource-id "/subscriptions/YOUR_SUBSCRIPTION_ID/resourceGroups/YOUR_RESOURCE_GROUP/providers/Microsoft.Network/virtualNetworkGateways/YOUR_GATEWAY_NAME" --metric "TunnelS2SBandwidth" --interval 5m --timespan 2023-10-27T10:00:00Z/2023-10-27T11:00:00Z

# List diagnostic settings
az monitor diagnostic-settings list --resource /subscriptions/YOUR_SUBSCRIPTION_ID/resourceGroups/YOUR_RESOURCE_GROUP/providers/Microsoft.Network/virtualNetworkGateways/YOUR_GATEWAY_NAME

Azure PowerShell

Azure PowerShell offers similar capabilities for monitoring and log retrieval.

# Get VPN gateway metrics
Get-AzMetric -ResourceId "/subscriptions/YOUR_SUBSCRIPTION_ID/resourceGroups/YOUR_RESOURCE_GROUP/providers/Microsoft.Network/virtualNetworkGateways/YOUR_GATEWAY_NAME" -MetricName "TunnelP2SBandwidth" -TimeGrain 00:05:00 -StartTime 2023-10-27T10:00:00Z -EndTime 2023-10-27T11:00:00Z

# Get diagnostic settings
Get-AzDiagnosticSetting -ResourceId "/subscriptions/YOUR_SUBSCRIPTION_ID/resourceGroups/YOUR_RESOURCE_GROUP/providers/Microsoft.Network/virtualNetworkGateways/YOUR_GATEWAY_NAME"

Note: Replace placeholders like YOUR_SUBSCRIPTION_ID, YOUR_RESOURCE_GROUP, and YOUR_GATEWAY_NAME with your actual Azure resource details.

Common Monitoring Scenarios

High Latency: Monitor tunnel bandwidth and packet loss metrics. Investigate potential network congestion or configuration issues on-premises.
Intermittent Disconnections: Review TunnelDiagnosticLog for rekeying failures or tunnel establishment errors. Check shared key configurations and firewall rules.
Low Throughput: Examine bandwidth metrics for both P2S and S2S connections. Ensure the VPN Gateway SKU is appropriate for your workload and that on-premises bandwidth is not a bottleneck.
Connection Issues: Use TunnelConnectionDiagnosticLog to pinpoint specific connection failures and examine the underlying reasons.

Effective monitoring of your Azure VPN Gateway ensures the stability, security, and performance of your network connectivity.