This topic describes the monitoring metrics for Classic Load Balancer (CLB). You can query these metrics to check the status, load, and performance of your CLB instances and troubleshoot issues such as request timeouts and traffic throttling.
Usage notes
To make CloudMonitor API calls for a CLB instance, you must obtain its Namespace, Period, MetricName, and Dimensions.
Set Namespace to
acs_slb_dashboard.The default value of Period is 60 seconds. You can also set this parameter to a multiple of 60.
Set Dimensions to a JSON string. Example:
[{"instanceId":"lb-bp1r92vzpemy099f******", "port":"80", "vip":"121.43.**.**"}]. In Dimensions, `instanceId` specifies the ID of the CLB instance, `port` specifies the listener port, and `vip` specifies the service address.
CLB monitoring metrics
Metrics that you can view in the console or using an API or SDK
Layer 4 monitoring metrics
Metric category | Metric | Description | MetricName | Dimensions | Statistics |
Instance Connection Class | New connections to instance | The number of new TCP and UDP connections that a CLB instance processes per second. Unit: Count/s | InstanceNewConnection | instanceId | Average, Minimum, Maximum |
Dropped connections on instance | The number of TCP and UDP connections that are dropped by a CLB instance per second. Unit: Count/s | InstanceDropConnection | instanceId | Average, Minimum, Maximum | |
Active connections to instance | The number of TCP connections in the ESTABLISHED state on a CLB instance. Unit: Count Note If you use persistent connections, one connection can transfer multiple file requests at the same time. | InstanceActiveConnection | instanceId | Average, Minimum, Maximum | |
Inactive connections to instance | The number of TCP connections that are not in the ESTABLISHED state and all UDP connections on a CLB instance. Unit: Count | InstanceInactiveConnection | instanceId | Average, Minimum, Maximum | |
Concurrent connections to instance | The number of all TCP and UDP connections that a CLB instance processes. Unit: Count | InstanceMaxConnection | instanceId | Average, Minimum, Maximum | |
Instance bandwidth/traffic metrics | Inbound traffic to instance | The volume of TCP and UDP data that a CLB instance receives per second. Unit: bit/s | InstanceTrafficRX | instanceId | Average, Minimum, Maximum |
Outbound traffic from instance | The volume of TCP and UDP data that a CLB instance sends per second. Unit: bit/s | InstanceTrafficTX | instanceId | Average, Minimum, Maximum | |
Inbound packets to instance | The number of TCP and UDP data packets that a CLB instance receives per second. Unit: Count/s | InstancePacketRX | instanceId | Average, Minimum, Maximum | |
Outbound packets from instance | The number of TCP and UDP data packets that a CLB instance sends per second. Unit: Count/s | InstancePacketTX | instanceId | Average, Minimum, Maximum | |
Dropped inbound traffic on instance | The volume of TCP and UDP data that a CLB instance fails to receive per second. Unit: bit/s | InstanceDropTrafficRX | instanceId | Average, Minimum, Maximum | |
Dropped outbound traffic on instance | The volume of TCP and UDP data that a CLB instance fails to send per second. Unit: bit/s | InstanceDropTrafficTX | instanceId | Average, Minimum, Maximum | |
Dropped inbound packets on instance | The number of TCP and UDP data packets that a CLB instance fails to receive per second. Unit: Count/s | InstanceDropPacketRX | instanceId | Average, Minimum, Maximum | |
Dropped outbound packets on instance | The number of TCP and UDP data packets that a CLB instance fails to send per second. Unit: Count/s | InstanceDropPacketTX | instanceId | Average, Minimum, Maximum | |
Listener Connection Class | New connections to listener | The number of new TCP or UDP connections that the listener port processes per second. Unit: Count/s | NewConnection | instanceId, port, vip | Average, Minimum, Maximum |
Dropped connections on listener | The number of TCP or UDP connections that are dropped by the listener port per second. Unit: Count/s | DropConnection | instanceId, port, vip | Average, Minimum, Maximum | |
Active connections to listener | The number of TCP connections in the ESTABLISHED state on the listener port. Unit: Count Note If you use persistent connections, one connection can transfer multiple file requests at the same time. | ActiveConnection | instanceId, port, vip | Average, Minimum, Maximum | |
Inactive connections to listener | The number of TCP connections that are not in the ESTABLISHED state or all UDP connections on the listener port. Unit: Count | InactiveConnection | instanceId, port, vip | Average, Minimum, Maximum | |
Concurrent connections to listener | The number of all TCP or UDP connections that the listener port processes. Unit: Count | MaxConnection | instanceId, port, vip | Average, Minimum, Maximum | |
Listener bandwidth/traffic metrics | Inbound traffic to listener | The volume of TCP or UDP data that the listener port receives per second. Unit: bit/s | TrafficRXNew | instanceId, port, vip | Average, Minimum, Maximum |
Outbound traffic from listener | The volume of TCP or UDP data that the listener port sends per second. Unit: bit/s | TrafficTXNew | instanceId, port, vip | Average, Minimum, Maximum | |
Inbound packets to listener | The number of TCP or UDP data packets that the listener port receives per second. Unit: Count/s | PacketRX | instanceId, port, vip | Average, Minimum, Maximum | |
Outbound packets from listener | The number of TCP or UDP data packets that the listener port sends per second. Unit: Count/s | PacketTX | instanceId, port, vip | Average, Minimum, Maximum | |
Dropped inbound traffic on listener | The volume of TCP or UDP data that the listener port fails to receive per second. Unit: bit/s | DropTrafficRX | instanceId, port, vip | Average, Minimum, Maximum | |
Dropped outbound traffic on listener | The volume of TCP or UDP data that the listener port fails to send per second. Unit: bit/s | DropTrafficTX | instanceId, port, vip | Average, Minimum, Maximum | |
Dropped inbound packets on listener | The number of TCP or UDP data packets that the listener port fails to receive per second. Unit: Count/s | DropPacketRX | instanceId, port, vip | Average, Minimum, Maximum | |
Dropped outbound packets on listener | The number of TCP or UDP data packets that the listener port fails to send per second. Unit: Count/s | DropPacketTX | instanceId, port, vip | Average, Minimum, Maximum | |
Listener health check metrics | Number of healthy backend ECS instances | The number of backend ECS instances that are in the Normal state on the listener port. Unit: Count | HeathyServerCount | instanceId, port, vip | Average, Minimum, Maximum |
Number of unhealthy backend ECS instances | The number of backend ECS instances that are in the Abnormal state on the listener port. Unit: Count | UnhealthyServerCount | instanceId, port, vip | Average, Minimum, Maximum |
Layer 7 monitoring metrics
Metric category | Metric | Description | MetricName | Dimensions | Statistics |
Instance connection metrics | RT of Layer 7 instance | The time that elapses from when a client sends a request to when the client receives a response from a backend server through a CLB instance. Unit: ms | InstanceRt | instanceId | Average |
Upstream RT of Layer 7 instance | The time that elapses from when a CLB instance forwards a request to a backend server to when the CLB instance receives a response. Unit: ms | InstanceUpstreamRt | instanceId | Average | |
Instance request metrics | QPS of Layer 7 instance | The number of HTTP or HTTPS requests that a CLB instance can process per second. Unit: Count/s | InstanceQps | instanceId | Average |
Instance status code metrics | 2xx status codes of Layer 7 instance | The number of 2xx success response status codes that are returned from a backend server to a client through a CLB instance per second. Unit: Count/s | InstanceStatusCode2xx | instanceId | Average |
3xx status codes of Layer 7 instance | The number of 3xx redirection status codes that are returned from a backend server to a client through a CLB instance per second. Unit: Count/s | InstanceStatusCode3xx | instanceId | Average | |
4xx status codes of Layer 7 instance | The number of 4xx client error status codes that are returned from a backend server to a client through a CLB instance per second. Unit: Count/s | InstanceStatusCode4xx | instanceId | Average | |
5xx status codes of Layer 7 instance | The number of 5xx server error status codes that are returned from a backend server to a client through a CLB instance per second. Unit: Count/s | InstanceStatusCode5xx | instanceId | Average | |
Other status codes of Layer 7 instance | The number of status codes other than 2xx, 3xx, 4xx, and 5xx that are returned from a backend server to a client through a CLB instance per second. Unit: Count/s | InstanceStatusCodeOther | instanceId | Average | |
Backend instance status code metrics | UpstreamCode4xx of Layer 7 instance | The number of 4xx client error status codes that are returned from a backend server to a CLB instance per second. Unit: Count/s | InstanceUpstreamCode4xx | instanceId | Average |
UpstreamCode5xx of Layer 7 instance | The number of 5xx server error status codes that are returned from a backend server to a CLB instance per second. Unit: Count/s | InstanceUpstreamCode5xx | instanceId | Average | |
Listener connection metrics | RT of Layer 7 listener | The time that elapses from when a client sends a request to when the client receives a response from a backend server through the listener port. Unit: ms | Rt | instanceId, port, vip | Average |
Upstream RT of Layer 7 listener | The time that elapses from when a CLB instance forwards a request through the listener port to a backend server to when the CLB instance receives a response. Unit: ms | UpstreamRt | instanceId, port, vip | Average | |
Request Listener Class | QPS of Layer 7 listener | The number of HTTP or HTTPS requests that the listener port can process per second. Unit: Count/s | Qps | instanceId, port, vip | Average |
Listener status code metrics | 2xx status codes of Layer 7 listener | The number of 2xx success response status codes that are returned from a backend server to a client through the listener port per second. Unit: Count/s | StatusCode2xx | instanceId, port, vip | Average |
3xx status codes of Layer 7 listener | The number of 3xx redirection status codes that are returned from a backend server to a client through the listener port per second. Unit: Count/s | StatusCode3xx | instanceId, port, vip | Average | |
4xx status codes of Layer 7 listener | The number of 4xx client error status codes that are returned from a backend server to a client through the listener port per second. Unit: Count/s | StatusCode4xx | instanceId, port, vip | Average | |
5xx status codes of Layer 7 listener | The number of 5xx server error status codes that are returned from a backend server to a client through the listener port per second. Unit: Count/s | StatusCode5xx | instanceId, port, vip | Average | |
Other status codes of Layer 7 listener | The number of status codes other than 2xx, 3xx, 4xx, and 5xx that are returned from a backend server to a client through the listener port per second. Unit: Count/s | StatusCodeOther | instanceId, port, vip | Average | |
Backend listener status code metrics | UpstreamCode4xx of Layer 7 listener | The number of 4xx client error status codes that are returned from a backend server to a CLB instance through the listener port per second. Unit: Count/s | UpstreamCode4xx | instanceId, port, vip | Average |
UpstreamCode5xx of Layer 7 listener | The number of 5xx server error status codes that are returned from a backend server to a CLB instance through the listener port per second. Unit: Count/s | UpstreamCode5xx | instanceId, port, vip | Average |
Metrics that you can view only using an API or SDK
Layer 4 monitoring metrics
Metric category | Metric | Description | MetricName | Dimensions | Statistics |
Instance Connection Class | Instance connection utilization | The ratio of the number of current connections to the maximum number of connections for a CLB instance. Unit: % | InstanceMaxConnectionUtilization | instanceId | Average, Maximum, Minimum |
New instance connection utilization | The ratio of the number of new connections to the maximum number of new connections for a CLB instance. Unit: % | InstanceNewConnectionUtilization | instanceId | Average, Maximum, Minimum |
Layer 7 monitoring metrics
Metric category | Metric | Description | MetricName | Dimensions | Statistics |
Instance Request Class | QPS utilization of Layer 7 instance | The ratio of the actual number of requests that a CLB instance processes to the maximum number of requests that the instance can process. Unit: % | InstanceQpsUtilization | instanceId | Average, Maximum, Minimum |
FAQ
What are the differences between monitoring data and billing data?
Factor | Monitoring data | Billing data |
Calculation and generation method | The Server Load Balancer system collects traffic data for monitoring at a 1-minute granularity and reports the data to CloudMonitor. | Metering data for billing is collected at the same granularity. The Server Load Balancer system reports the hourly aggregated value to the billing system for bill settlement. |
Real-time performance | Server Load Balancer provides real-time monitoring data. However, a slight delay is inevitable during data collection, calculation, and display. Although the delay is minimal, it can cause discrepancies between monitoring data and billing data. | Metering data used for billing allows a delay of up to 3 hours. For example, metering data generated from 01:00 to 02:00 is typically reported by Server Load Balancer to the billing system before 03:00. However, the system allows the report to be delayed until 05:00. This can cause discrepancies between billing data and monitoring data. |
Purpose | The purpose of monitoring is to observe the running status of an instance. This lets you detect anomalies and take targeted actions to resolve issues. | The purpose of metering is to calculate charges based on the actual resource consumption of an instance. For billing, rely on the data from the billing system, not the monitoring data. |
References
To learn about the differences between monitoring data and billing data, see Monitoring data and billing data.
To view the monitoring information of a CLB instance, see View monitoring information of a CLB instance.
To configure alert rules for a CLB instance, see Configure alert rules.