---
aliases:
  - ../high-availability/enable-alerting-ha/
  - ../unified-alerting/high-availability/
description: Enable alerting high availability
keywords:
  - grafana
  - alerting
  - tutorials
  - ha
  - high availability
title: Enable alerting high availability
weight: 300
---

# Enable alerting high availability

You can enable alerting high availability support by updating the Grafana configuration file. If you run Grafana in a Kubernetes cluster, additional steps are required. Both options are described below.

## Enable alerting high availability in Grafana

### Before you begin

Since gossiping of notifications and silences uses both TCP and UDP port `9094`, ensure that each Grafana instance is able to accept incoming connections on these ports.

**To enable high availability support:**

1. In your custom configuration file ($WORKING_DIR/conf/custom.ini), go to the `[unified_alerting]` section.
2. Set `[ha_peers]` to the number of hosts for each Grafana instance in the cluster (using a format of host:port), for example, `ha_peers=10.0.0.5:9094,10.0.0.6:9094,10.0.0.7:9094`.
   You must have at least one (1) Grafana instance added to the [`[ha_peer]` section.
3. Set `[ha_listen_address]` to the instance IP address using a format of `host:port` (or the [Pod's](https://kubernetes.io/docs/concepts/workloads/pods/) IP in the case of using Kubernetes).
   By default, it is set to listen to all interfaces (`0.0.0.0`).

## Enable alerting high availability using Kubernetes

If you are using Kubernetes, you can expose the pod IP [through an environment variable](https://kubernetes.io/docs/tasks/inject-data-application/environment-variable-expose-pod-information/) via the container definition.

```bash
env:
- name: POD_IP
  valueFrom:
    fieldRef:
      fieldPath: status.podIP
```

1. Add the port 9094 to the Grafana deployment:

```yaml
ports:
  - containerPort: 3000
    name: http-grafana
    protocol: TCP
  - containerPort: 9094
    name: grafana-alert
    protocol: TCP
```

2. Add the environment variables to the Grafana deployment:

```yaml
env:
  - name: POD_IP
    valueFrom:
      fieldRef:
        fieldPath: status.podIP
```

3. Create a headless service that returns the pod IP instead of the service IP, which is what the `ha_peers` need:

```yaml
apiVersion: v1
kind: Service
metadata:
  name: grafana-alerting
  namespace: grafana
  labels:
    app.kubernetes.io/name: grafana-alerting
    app.kubernetes.io/part-of: grafana
spec:
  type: ClusterIP
  clusterIP: 'None'
  ports:
    - port: 9094
  selector:
    app: grafana
```

4. Make sure your grafana deployment has the label matching the selector, e.g. `app:grafana`.

5. Add in the grafana.ini:

```bash
[unified_alerting]
enabled = true
ha_listen_address = "${POD_IP}:9094"
ha_peers = "grafana-alerting.grafana:9094"
ha_advertise_address = "${POD_IP}:9094"
```