Azure Load Balancer monitoring data reference
This article contains all the monitoring reference information for this service.
See Monitor Azure Load Balancer for details on the data you can collect for Load Balancer and how to use it.
Metrics
This section lists all the automatically collected platform metrics for this service. These metrics are also part of the global list of all platform metrics supported in Azure Monitor.
For information on metric retention, see Azure Monitor Metrics overview.
Supported metrics for Microsoft.Network/loadBalancers
The following table lists the metrics available for the Microsoft.Network/loadBalancers resource type.
- All columns might not be present in every table.
- Some columns might be beyond the viewing area of the page. Select Expand table to view all available columns.
Table headings
- Category - The metrics group or classification.
- Metric - The metric display name as it appears in the Azure portal.
- Name in REST API - The metric name as referred to in the REST API.
- Unit - Unit of measure.
- Aggregation - The default aggregation type. Valid values: Average (Avg), Minimum (Min), Maximum (Max), Total (Sum), Count.
- Dimensions - Dimensions available for the metric.
- Time Grains - Intervals at which the metric is sampled. For example,
PT1Mindicates that the metric is sampled every minute,PT30Mevery 30 minutes,PT1Hevery hour, and so on. - DS Export- Whether the metric is exportable to Azure Monitor Logs via diagnostic settings. For information on exporting metrics, see Create diagnostic settings in Azure Monitor.
| Metric | Name in REST API | Unit | Aggregation | Dimensions | Time Grains | DS Export |
|---|---|---|---|---|---|---|
| Allocated SNAT Ports Total number of SNAT ports allocated within time period |
AllocatedSnatPorts |
Count | Average | FrontendIPAddress, BackendIPAddress, ProtocolType |
PT1M | No |
| Byte Count Total number of Bytes transmitted within time period |
ByteCount |
Bytes | Total | FrontendIPAddress, FrontendPort, Direction |
PT1M | Yes |
| Health Probe Status Average Load Balancer health probe status per time duration |
DipAvailability |
Count | Average | ProtocolType, BackendPort, FrontendIPAddress, FrontendPort, BackendIPAddress |
PT1M | Yes |
| Health Probe Status Azure Cross-region Load Balancer backend health and status per time duration |
GlobalBackendAvailability |
Count | Average | FrontendIPAddress, FrontendPort, BackendIPAddress, ProtocolType |
PT1M | Yes |
| Packet Count Total number of Packets transmitted within time period |
PacketCount |
Count | Total | FrontendIPAddress, FrontendPort, Direction |
PT1M | Yes |
| SNAT Connection Count Total number of new SNAT connections created within time period |
SnatConnectionCount |
Count | Total | FrontendIPAddress, BackendIPAddress, ConnectionState |
PT1M | Yes |
| SYN Count Total number of SYN Packets transmitted within time period |
SYNCount |
Count | Total | FrontendIPAddress, FrontendPort, Direction |
PT1M | Yes |
| Used SNAT Ports Total number of SNAT ports used within time period |
UsedSnatPorts |
Count | Average | FrontendIPAddress, BackendIPAddress, ProtocolType |
PT1M | No |
| Data Path Availability Average Load Balancer data path availability per time duration |
VipAvailability |
Count | Average | FrontendIPAddress, FrontendPort |
PT1M | Yes |
Load balancer metrics
This table includes additional information about metrics from the Microsoft.Network/loadBalancers table:
| Metric | Resource type | Description |
|---|---|---|
| Allocated SNAT ports | Public load balancer | Standard Load Balancer reports the number of SNAT ports allocated per backend instance. |
| Byte count | Public and internal load balancer | Standard Load Balancer reports the data processed per front end. You might notice that the bytes aren't distributed equally across the backend instances. This behavior is expected as Azure's Load Balancer algorithm is based on flows. |
| Health probe status | Public and internal load balancer | Standard Load Balancer uses a distributed health-probing service that monitors your application endpoint's health according to your configuration settings. This metric provides an aggregate or per-endpoint filtered view of each instance endpoint in the load balancer pool. You can see how Load Balancer views the health of your application, as indicated by your health probe configuration. |
| SNAT connection count | Public load balancer | Standard Load Balancer reports the number of outbound flows that are masqueraded to the Public IP address front end. Source network address translation (SNAT) ports are an exhaustible resource. This metric can give an indication of how heavily your application is relying on SNAT for outbound originated flows. Counters for successful and failed outbound SNAT flows are reported and can be used to troubleshoot and understand the health of your outbound flows. |
| SYN count (synchronize) | Public and internal load balancer | Standard Load Balancer doesn’t terminate Transmission Control Protocol (TCP) connections or interact with TCP or User Data-gram Packet (UDP) flows. Flows and their handshakes are always between the source and the virtual machine instance. To better troubleshoot your TCP protocol scenarios, you can make use of SYN packets counters to understand how many TCP connection attempts are made. The metric reports the number of TCP SYN packets that were received. |
| Used SNAT ports | Public load balancer | Standard Load Balancer reports the number of SNAT ports that are utilized per backend instance. |
| Data path availability | Public and internal load balancer | Standard Load Balancer continuously exercises the data path from within a region to the load balancer front end, all the way to the SDN stack that supports your virtual machine. As long as healthy instances remain, the measurement follows the same path as your application's load-balanced traffic. The data path that your customer's use is also validated. The measurement is invisible to your application and doesn't interfere with other operations. |
Global load balancer metrics
This table includes additional information about global metrics from the Microsoft.Network/loadBalancers table:
| Metric | Resource type | Description |
|---|---|---|
| Health probe status | Public global load balancer | Global load balancer uses a distributed health-probing service that monitors your application endpoint's health according to your configuration settings. This metric provides an aggregate or per-endpoint filtered view of each instance regional load balancer in the global load balancer's backend pool. You can see how global load balancer views the health of your application, as indicated by your health probe configuration. |
| Data path availability | Public global load balancer | Global load balancer continuously exercises the data path from within a region to the load balancer front end, all the way to the SDN stack that supports your virtual machine. As long as healthy instances remain, the measurement follows the same path as your application's load-balanced traffic. The data path that your customer's use is also validated. The measurement is invisible to your application and doesn't interfere with other operations. |
Note
Bandwidth-related metrics such as SYN packet, byte count, and packet count doesn't capture any traffic to an internal load balancer by using a UDR, such as from an NVA or firewall.
Max and min aggregations are not available for the SYN count, packet count, SNAT connection count, and byte count metrics. Count aggregation is not recommended for Data path availability and health probe status. Use average instead for best represented health data.
Metric dimensions
For information about what metric dimensions are, see Multi-dimensional metrics.
This service has the following dimensions associated with its metrics.
| Dimension | Name | Description |
|---|---|---|
| BackendIPAddress | Backend IP | The backend IP address of one or more relevant load balancing rules |
| BackendPort | Backend Port | The backend port of one or more relevant load balancing rules |
| ConnectionState | Connection state | The state of SNAT connection. The state can be pending, successful, or failed |
| Direction | Direction | The direction traffic is flowing. This value can be inbound or outbound. |
| FrontendIPAddress | Frontend IP | The frontend IP address of one or more relevant load balancing rules |
| FrontendPort | Frontend Port | The frontend port of one or more relevant load balancing rules |
| ProtocolType | Protocol Type | The protocol of the relevant load balancing rule. The protocol can be TCP or UDP |
Resource logs
This section lists the types of resource logs you can collect for this service. The section pulls from the list of all resource logs category types supported in Azure Monitor.
Supported resource logs for Microsoft.Network/loadBalancers
| Category | Category display name | Log table | Supports basic log plan | Supports ingestion-time transformation | Example queries | Costs to export |
|---|---|---|---|---|---|---|
LoadBalancerHealthEvent |
Load Balancer Health Event | ALBHealthEvent Table of events related to the availability and health of a load balancer resource. |
Yes | No | Queries | Yes |
Azure Monitor Logs tables
This section lists the Azure Monitor Logs tables relevant to this service, which are available for query by Log Analytics using Kusto queries. The tables contain resource log data and possibly more depending on what is collected and routed to them.
Load Balancer Microsoft.Network/LoadBalancers
Activity log
The linked table lists the operations that can be recorded in the activity log for this service. These operations are a subset of all the possible resource provider operations in the activity log.
For more information on the schema of activity log entries, see Activity Log schema.
Related content
- See Monitor Azure Load Balancer for a description of monitoring Load Balancer.
- See Monitor Azure resources with Azure Monitor for details on monitoring Azure resources.