ApsaraDB for ClickHouse:Configure an alert rule

Create an alert rule

If your cluster meets either of the following conditions, follow the steps in Create an alert rule in the old console instead:

Your cluster was created before December 1, 2021.

Your cluster is deployed in the China (Qingdao) or China (Hohhot) region.

1. Log on to the ApsaraDB for ClickHouse console.

2. In the top navigation bar, select the region where your cluster is deployed.

3. On the Clusters page, click the Clusters of Community-compatible Edition tab or the Enterprise Edition Clusters tab, then click the cluster ID.

4. In the left-side navigation pane, click Monitoring and Alerting.

5. Click Cluster Alerting.

6. Click Create ClickHouseAlert Rule (for Community-compatible Edition) or Create Enterprise EditionClickHouseAlert Rule (for Enterprise Edition).

7. On the rule creation page, set Check type to Static Threshold or Custom PromQL, then configure the parameters described below.

   Static threshold

   Use this check type to monitor a preset metric against a fixed numeric threshold.

   Parameter	Description	Example
   Alert rule name	A name that identifies the alert rule.	CPU utilization alert
   Check type	Set to Static Threshold.	Static Threshold
   Cluster	The cluster to monitor.	cc-bp1lxbo89u95****
   Alert contact group	The group that receives alert notifications. Available groups vary by Prometheus instance type.	ClickHouse
   Alert metric	The metric to monitor. Available metrics vary by alert contact group.	cpu_usage
   Alert condition	The condition that triggers an alert event.	When cpu usage > 80%, trigger alert
   Filter conditions	Restricts the alert rule to a specific resource scope.	No Filter
   Data Preview	Displays the PromQL statement derived from your alert condition, along with a time series graph of the metric. Use this to verify the condition behaves as expected before saving: the threshold appears as a red line; data points above the threshold appear in dark red, and data points below appear in blue. Hover over the curve to inspect values at a specific point in time. You can also select a time period on the time series curve to view the time series curve of the selected time period.	—
   Duration	Controls when an alert event is generated: If the alert condition is met triggers immediately when the threshold is reached; If the alert condition is met continuously for N minutes triggers only after the threshold is exceeded for at least N consecutive minutes.	1
   Alert level	Severity of the alert. Valid values: Default, P4, P3, P2, P1 (ascending severity).	P2
   Alert message	The notification message sent to contacts. Supports Go template syntax and custom variables.	node: {{$labels.pod_name}} CPU usage {{$labels.metrics_params_opt_label_value}} {{$labels.metrics_params_value}}%, current value {{ printf "%.2f" $value }}%
   Alert notification — Simple mode	Notification objects: the recipients. Notification period: only alerts generated within this time window are sent. Whether to resend notifications: controls resend behavior.	—
   Alert notification — Standard mode	Select a notification policy from the Specify notification policy drop-down list. > Important After you select a notification policy, the alert events generated by this rule can be matched by the selected policy and alerts can be generated. The alert events may also be matched by other notification policies that use fuzzy match, and alerts may be generated. One or more alert events can be matched by one or more notification policies. Click Create notification policy to create a new one. For details, see Create and manage a notification policy.	Do Not Specify Notification Policy
   Alert check cycle	How often the rule checks whether the alert condition is met. Default: 1 minute. Minimum: 1 minute.	1 minute
   Check after the data is complete	Whether to run the check only after data is fully collected, transmitted, and written to storage. Default: Yes.	Yes
   Tags	Tags attached to the alert rule for matching notification policies.	—
   Annotations	Additional metadata for the alert rule.	—

   Custom PromQL

   Use this check type to write a PromQL expression and alert on any metric, including custom ones.

   Parameter	Description	Example
   Alert rule name	A name that identifies the alert rule.	Pod CPU utilization exceeds 8%
   Check type	Set to Custom PromQL.	Custom PromQL
   Cluster	The cluster to monitor.	cc-bp1lxbo89u95****
   Reference alert contact group	The group that receives alert notifications. Available groups vary by Prometheus instance type.	ClickHouse
   Reference metrics	Optional. Select a common metric to pre-fill the Custom PromQL statements field. Available metrics vary by Prometheus instance type.	http_conn_usage_count
   Custom PromQL statements	The PromQL expression that defines the alert condition.	clickhouse_http_conn_usage_count{} > 1000
   Data Preview	Displays a time series graph of the metric based on your PromQL expression. Use this to confirm the expression returns the expected data before saving.	—
   Duration	Controls when an alert event is generated: If the alert condition is met triggers immediately; If the alert condition is met continuously for N minutes requires N consecutive minutes above the threshold.	1
   Alert level	Severity of the alert. Valid values: Default, P4, P3, P2, P1 (ascending severity).	Default
   Alert message	The notification message sent to contacts. Supports Go template syntax and custom variables.	Namespace: {{$labels.namespace}} / Pod: {{$labels.pod_name}} / The utilization of the {{$labels.device}} disk exceeds 90%. Current value: {{ printf "%.2f" $value }}%
   Alert notification — Simple mode	Notification objects: the recipients. Notification period: only alerts generated within this time window are sent. Whether to resend notifications: controls resend behavior.	—
   Alert notification — Standard mode	Select a notification policy from the Specify notification policy drop-down list. Click Create notification policy to create a new one. For details, see Create and manage a notification policy.	Do Not Specify Notification Policy
   Alert check cycle	How often the rule checks whether the alert condition is met. Default: 1 minute. Minimum: 1 minute.	1 minute
   Check after the data is complete	Whether to run the check only after data is fully collected, transmitted, and written to storage. Default: Yes.	Yes
   Tags	Tags attached to the alert rule for matching notification policies.	—
   Annotations	Additional metadata for the alert rule.	—

8. Click Completed.

Create an alert rule using CloudMonitor

1. Log on to the CloudMonitor console.

2. In the left-side navigation pane, choose Alerts > Alert Rules.

3. On the Alert Rules page, click Create Alert Rule.

4. In the Create Alert Rule panel, configure the following parameters.

1. Click OK. The alert rule takes effect immediately.