Application Real-Time Monitoring Service:Static thresholds

Prerequisites

Your application is monitored by Application Monitoring. For more information, see Application Monitoring overview.

Procedure

1. Log on to the ARMS console.

2. In the left-side navigation pane, choose Application Monitoring > Application Monitoring Alert Rules. On the Application Monitoring Alert Rules page, click Create Alert Rule.

3. On the Create Application Monitoring Alert Rule page, set the Alert Rule Name parameter and set the Alert Detection Type parameter to Threshold Detection.

   Note

   For information about how to configure dynamic thresholds, see Dynamic thresholds.

4. In the Alert Contact section, specify the application, metric type, and filter condition.

   Parameter	Description
   Select Applications	Select the application that you want to monitor. You can select multiple applications or all applications.
   Automatically apply this alert rule to newly created applications	Specify whether to automatically apply this alert rule to applications that are later integrated into Application Monitoring.
   Metric Type	Select the type of the metric that you want to detect. For more information, see Alert metrics. Note The values of the Alert Condition and Filter Condition parameters vary with the value of the Metric Type parameter.
   Filter Condition	Further filter the metric data to narrow down the monitoring scope. Specify the condition for filtering data related to the dimension. Valid values: Traverse: The alert content shows the dimension content that actually triggers the alert. No Dimension: The alert content shows the sum of all values of the dimension. =: The alert content shows only the specified values of the dimension. !=: The alert content shows all values of the dimension except the specified values. Contain: The alert content contains the specified values of the dimension. Do Not Contain: The alert content contains all values of the dimension except the specified values. Match Regular Expression: The alert content shows only the dimension content specified by the regular expression.

5. In the Alert rules section, set the Alert trigger mode and Alert Condition parameters.

   Parameter	Description
   Alert trigger mode	Single Condition: Specify one condition. Multiple Conditions: Set the Alert Triggering Rules parameter to specify multiple conditions. Valid values: Meet All the Following Rules: Alerts are triggered only if all the conditions are met. Meet One of the Following Rules: Alerts are triggered if one of the conditions is met.
   Alert Condition	Single Condition: Configure an expression. The following alert levels are available in ascending order: P4, P3, P2, and P1. You can specify different thresholds for the alert levels based on your business requirements. You do not need to configure thresholds for all levels. In the following examples, thresholds are configured for JVM full GCs in the last 5 minutes. Example 1: If the average number of GCs is greater than 1, a P4 alert is triggered. If the average number of GCs is greater than 2, a P3 alert is triggered. If the average number of GCs is greater than 5, a P2 alert is triggered. If the average number of GCs is greater than 10, a P1 alert is triggered. Example 2: If the average number of GCs is greater than 1, a P4 alert is triggered. Multiple Conditions: Click Add Condition to configure an alert condition. Example: Alert Triggering Rule: Set the value to Meet All the Following Rules. Condition 1: The average error rate in the last 2 minutes is greater than or equal to 5%. Condition 2: The number of calls in the last 2 minutes is greater than or equal to 200. In Multiple Conditions mode, the Alert Level parameter is required. The following alert levels are available in ascending order: P4, P3, P2, and P1.
   Enter P4 recommended threshold	You can adjust the threshold values based on the metrics shown in the chart preview section. To apply the rule to multiple applications, click the icon next to Application to generate different recommended thresholds for the applications. ARMS uses an intelligent algorithm to generate recommended thresholds based on the historical metric data. For more information, see the Recommended thresholds section.
   Alert Quantity Prediction	View the number of alerts that are expected to be triggered within the time period. Click the number to query the data that is expected to trigger the alerts at the historical points in time. Each time you create or modify an alert rule, we recommend that you use the alert prediction feature. This feature uses an anomaly detection algorithm to analyze historical data and predict the number of alerts within the specified time period. Then, you can adjust dynamic thresholds based on the prediction results. For more information, see the Alert prediction section.

6. Configure the Notification Policy parameter and parameters in the Advanced Alert Settings section.

   Parameter	Description
   Notification Policy	Do Not Specify Notification Policy: If alerts are triggered, no notification is sent. Notifications are sent only when the matching rules of a notification policy is triggered. Specify a notification policy: If you specify a notification policy, ARMS sends notifications by using the notification method specified in the notification policy. You can select an existing notification policy or create a notification policy. For more information, see Create and manage a notification policy.
   Advanced Alert Settings
   No data	This parameter is used to fix data anomalies, such as missing data, abnormal composite metrics, and abnormal period-over-period comparison results. If data anomalies can be fixed, the data is automatically changed to 0 or 1, or the alert is not triggered. For more information, see Terms.

7. Click Save.

Recommended thresholds

ARMS uses an intelligent algorithm to analyze the historical data and generate recommended static thresholds based on the specified application, interface, and metric. In addition, a chart is generated for preview. You can compare the threshold values and estimated values, and then adjust the threshold values.

Scenarios

• Assume that alerts related to a specific metric are frequently triggered, but the system is running as expected. This may be because the threshold is not properly set, or not suitable for certain applications or interfaces. In this case, you can use the recommended thresholds feature to adjust the thresholds or configure different thresholds for different applications or interfaces.

• Assume that you need to configure different thresholds for a metric of a large number of applications and interfaces. You can use the intelligent algorithm and quickly configure recommended thresholds for the applications and interfaces.

Implementation

After you click Enter P4 recommended threshold, ARMS automatically pulls the metric data of each application and interface in the last three days. Then, ARMS uses the N-sigma algorithm to calculate the average value and variance for each metric. Assume that your business keeps steady and metrics are normally distributed. The probability of three standard deviations is low. In this case, a recommended threshold can be generated based on the average value and fluctuation of the metric within the last three days.

Among the alert levels, P4 has the lowest severity. A recommended P4 threshold indicates that the metric is slightly abnormal. You can take into account the P4 threshold and configure thresholds for other alert levels, including P1, P2, and P3.

Alert quantity prediction

The alert quantity prediction feature uses an algorithm to analyze historical data, display the time when historical alerts occur, and then predicts the number of alerts within a specified period of time. The feature helps you configure static thresholds or improve alert sensitivity for dynamic thresholds.

Implementation

Based on metric data in the last 24 hours, ARMS calculates the number of times that each threshold of a metric is exceeded to predict the quantity of alerts in the future. In addition, ARMS provides the metric details, including the specific time when each threshold is exceeded. You can adjust thresholds based on your business requirements.