Chapter 10. Managing alerts

1. Go to Observe Alerting Alerts in the OpenShift Dedicated web console.
2. For the alert that you want to silence, click and select Silence alert to open the Silence alert page with a default configuration for the chosen alert.

3. Optional: Change the default configuration details for the silence.

   Note

   You must add a comment before saving a silence.

4. To save the silence, click Silence.

1. Go to Observe <project_name> Alerts in the OpenShift Dedicated web console.
2. If necessary, expand the details for the alert by selecting a greater than symbol (>) next to the alert name.
3. Click the alert message in the expanded view to open the Alert details page for the alert.
4. Click Silence alert to open the Silence alert page with a default configuration for the alert.

5. Optional: Change the default configuration details for the silence.

   Note

   You must add a comment before saving a silence.

6. To save the silence, click Silence.

1. Go to Observe Alerting Silences in the OpenShift Dedicated web console.
2. Click Create silence.

3. On the Create silence page, set the schedule, duration, and label details for an alert.

   Note

   You must add a comment before saving a silence.

4. To create silences for alerts that match the labels that you entered, click Silence.

1. Go to Observe <project_name> Silences in the OpenShift Dedicated web console.
2. Click Create silence.

3. On the Create silence page, set the duration and label details for an alert.

   Note

   You must add a comment before saving a silence.

4. To create silences for alerts that match the labels that you entered, click Silence.

1. Go to Observe Alerting Silences.

2. For the silence you want to modify, click and select Edit silence.

   Alternatively, you can click Actions and select Edit silence on the Silence details page for a silence.

3. On the Edit silence page, make changes and click Silence. Doing so expires the existing silence and creates one with the updated configuration.

1. Go to Observe <project_name> Silences.

2. For the silence you want to modify, click and select Edit silence.

   Alternatively, you can click Actions and select Edit silence on the Silence details page for a silence.

3. On the Edit silence page, make changes and click Silence. Doing so expires the existing silence and creates one with the updated configuration.

1. Go to Observe Alerting Silences.
2. For the silence or silences you want to expire, select the checkbox in the corresponding row.

3. Click Expire 1 silence to expire a single selected silence or Expire <n> silences to expire multiple selected silences, where <n> is the number of silences you selected.

   Alternatively, to expire a single silence you can click Actions and select Expire silence on the Silence details page for a silence.

1. Go to Observe <project_name> Silences.
2. For the silence or silences you want to expire, select the checkbox in the corresponding row.

3. Click Expire 1 silence to expire a single selected silence or Expire <n> silences to expire multiple selected silences, where <n> is the number of silences you selected.

   Alternatively, to expire a single silence you can click Actions and select Expire silence on the Silence details page for a silence.

Procedure

1. Create a YAML file for alerting rules. In this example, it is called example-app-alerting-rule.yaml.

2. Add an alerting rule configuration to the YAML file. The following example creates a new alerting rule named example-alert. The alerting rule fires an alert when the version metric exposed by the sample service becomes 0:

   apiVersion: monitoring.coreos.com/v1
   kind: PrometheusRule
   metadata:
     name: example-alert
     namespace: ns1
   spec:
     groups:
     - name: example
       rules:
       - alert: VersionAlert 1
         for: 1m 2
         expr: version{job="prometheus-example-app"} == 0 3
         labels:
           severity: warning 4
         annotations:
           message: This is an example alert. 5

   1

   The name of the alerting rule you want to create.

   2

   The duration for which the condition should be true before an alert is fired.

   3

   The PromQL query expression that defines the new rule.

   4

   The severity that alerting rule assigns to the alert.

   5

   The message associated with the alert.

3. Apply the configuration file to the cluster:

   $ oc apply -f example-app-alerting-rule.yaml

Procedure

1. To list alerting rules in <project>:

   $ oc -n <project> get prometheusrule

2. To list the configuration of an alerting rule, run the following:

   $ oc -n <project> get prometheusrule <rule> -o yaml

Procedure

1. In the Administrator perspective, navigate to Observe Alerting Alerting rules.

2. Select the Platform and User sources in the Filter drop-down menu.

   Note

   The Platform source is selected by default.

Procedure

1. Create a YAML file for alert routing. The example in this procedure uses a file called example-app-alert-routing.yaml.

2. Add an AlertmanagerConfig YAML definition to the file. For example:

   apiVersion: monitoring.coreos.com/v1beta1
   kind: AlertmanagerConfig
   metadata:
     name: example-routing
     namespace: ns1
   spec:
     route:
       receiver: default
       groupBy: [job]
     receivers:
     - name: default
       webhookConfigs:
       - url: https://example.org/post

   Note

   For user-defined alerting rules, user-defined routing is scoped to the namespace in which the resource is defined. For example, a routing configuration defined in the AlertmanagerConfig object for namespace ns1 only applies to PrometheusRules resources in the same namespace.

3. Save the file.

4. Apply the resource to the cluster:

   $ oc apply -f example-app-alert-routing.yaml

   The configuration is automatically applied to the Alertmanager pods.

Procedure

1. Print the currently active Alertmanager configuration into the file alertmanager.yaml:

   $ oc -n openshift-user-workload-monitoring get secret alertmanager-user-workload --template='{{ index .data "alertmanager.yaml" }}' | base64 --decode > alertmanager.yaml

2. Edit the configuration in alertmanager.yaml:

   route:
     receiver: Default
     group_by:
     - name: Default
     routes:
     - matchers:
       - "service = prometheus-example-monitor" 1
       receiver: <receiver> 2
   receivers:
   - name: Default
   - name: <receiver>
     <receiver_configuration> 3

   1

   Specify labels to match your alerts. This example targets all alerts that have the service="prometheus-example-monitor" label.

   2

   Specify the name of the receiver to use for the alerts group.

   3

   Specify the receiver configuration.

3. Apply the new configuration in the file:

   $ oc -n openshift-user-workload-monitoring create secret generic alertmanager-user-workload --from-file=alertmanager.yaml --dry-run=client -o=yaml |  oc -n openshift-user-workload-monitoring replace secret --filename=-