Warning

This is a legacy feature. For new integrations, please use the Send Events API instead.

Google Managed Alertmanager

This guide shows how to forward alerts from Google Managed Prometheus (GMP) managed Alertmanager to Robusta using Robusta's generic Alertmanager webhook.

Note

Every alert must carry a cluster_name label. Set it to the Robusta cluster_name configured for the target cluster, or use external when the alerts do not belong to a specific runner.

For configuring metric querying from Google Managed Prometheus, see Google Managed Prometheus. For other Alertmanager integrations, see AlertManager - external or AlertManager - in-cluster.

Requirements

  • Robusta account_id and signing_key from your generated_values.yaml file.

  • A GMP workspace with managed Alertmanager enabled.

Configure the Alertmanager webhook

Apply the following Secret in the GMP namespace (default gmp-public). Replace <ACCOUNT_ID> and <SIGNING_KEY> with your credentials.

apiVersion: v1
kind: Secret
metadata:
  name: alertmanager
  namespace: gmp-public
type: Opaque
stringData:
  alertmanager.yaml: |
    receivers:
      - name: 'robusta'
        webhook_configs:
          - url: 'https://api.robusta.dev/integrations/generic/alertmanager'
            http_config:
              authorization:
                # Replace <ACCOUNT_ID> <SIGNING_KEY>, with your account_id and signing_key
                credentials: 'Bearer <ACCOUNT_ID> <SIGNING_KEY>'
            send_resolved: true

    route:
      receiver: 'robusta'
      group_by: ['...']
      group_wait: 1s
      group_interval: 1s
      repeat_interval: 4h

Ensure alerts include cluster_name

Use an OperatorConfig to add external labels to both collection and rule evaluation so every alert contains the required cluster_name label.

apiVersion: monitoring.googleapis.com/v1
kind: OperatorConfig
metadata:
  name: config
  namespace: gmp-public
collection:
  externalLabels:
    cluster_name: gmp-demo-cluster   # Match your Robusta cluster_name, or use "external"
    location: us-central1-c
    project_id: my-gcp-project
rules:
  externalLabels:
    cluster_name: gmp-demo-cluster
    location: us-central1-c
    project_id: my-gcp-project

Deploy a demo alert

Create a simple alerting rule to confirm delivery to Robusta.

apiVersion: monitoring.googleapis.com/v1
kind: Rules
metadata:
  name: test-alert
  namespace: gmp-public
spec:
  groups:
    - name: test
      interval: 30s
      rules:
        - alert: TestAlertForGCPAlertmanager
          expr: vector(1)
          for: 0m
          labels:
            severity: warning
          annotations:
            summary: "Test alert to verify Alertmanager webhook"
            description: "This is a test alert. Delete the Rules resource to stop it."

Optional: verify credentials with curl

You can manually validate the webhook and credentials by posting a sample alert:

curl -X POST 'https://api.robusta.dev/integrations/generic/alertmanager' \
  -H 'Authorization: Bearer <ACCOUNT_ID> <SIGNING_KEY>' \
  -H 'Content-Type: application/json' \
  -d '{
  "externalURL": "https://console.cloud.google.com/monitoring",
  "groupKey": "gmp/test-alert:gmp-webhook-test-001",
  "version": "1",
  "status": "firing",
  "receiver": "robusta",
  "alerts": [
    {
      "status": "firing",
      "startsAt": "2026-01-13T13:30:50Z",
      "endsAt": "1970-01-01T00:00:00Z",
      "generatorURL": "https://console.cloud.google.com/monitoring",
      "source": "GMP",
      "description": "Test alert to verify GMP Alertmanager webhook configuration",
      "fingerprint": "gmp-test-alert-12345",
      "annotations": {
        "summary": "GMP Webhook Test Alert",
        "description": "If you see this in Robusta, the webhook URL and credentials are working correctly!"
      },
      "labels": {
        "cluster_name": "external",
        "cluster": "external",
        "alertname": "GMP_WebhookTest",
        "severity": "warning",
        "namespace": "gmp-public",
        "source": "gmp-managed-alertmanager"
      }
    }
  ]
}'

You should see the test alert in Robusta shortly after applying the resources or running the curl command.