---
title: "Forward metrics with remote-write | Grafana Enterprise Metrics documentation"
description: "Forward metrics with remote-write Grafana Enterprise Metrics (GEM) allows for forwarding metrics evaluated from the Ruler to any Prometheus remote-write compatible backend. This works by loading rule groups into the Ruler with an extra config field as shown in the example below:"
---

# Forward metrics with remote-write

Grafana Enterprise Metrics (GEM) allows for forwarding metrics evaluated from the [Ruler](/docs/enterprise-metrics/latest/reference/mimir-arch/components/ruler/) to any Prometheus remote-write compatible backend.

This works by loading rule groups into the Ruler with an extra config field as shown in the example below:

console ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```console
# A regular Grafana Mimir rule group
groups:
  - name: group_one
    interval: 5m
    rules:
      - expr: 'rate(prometheus_remote_storage_samples_in_total[5m])'
        record: 'prometheus_remote_storage_samples_in_total:rate5m'
  - name: group_two
    interval: 1m
    rules:
      - expr: 'rate(prometheus_remote_storage_samples_in_total[1m])'
        record: 'prometheus_remote_storage_samples_in_total:rate1m'
    remote_write:
      - url: 'http://user:pass@example.com/api/v1/push'
```

In the above example, when `group_2` is loaded into Grafana Enterprise Metrics, the Ruler Module will evaluate the expression `rate(prometheus_remote_storage_samples_in_total[1m])` every `1m` and forward the generated metric with name `prometheus_remote_storage_samples_in_total:rate1m` to `example.com`. Meanwhile, `group_1` will continue to work as expected, the evaluated metric `prometheus_remote_storage_samples_in_total:rate5m` will be stored within the same GEM tenant that is running the Ruler.

### Configuration

#### Rule Storage

Remote write rules are compatible with the following backends:

- Azure Blob Storage
- GCS
- S3
- Swift

The following backends are not supported:

- local filesystem
- ConfigDB

#### Write-ahead log (WAL)

When a rule group is configured with a remote-write config, GEM buffers the generated metrics in a write-ahead log (WAL) before forwarding them to the remote-write endpoint. This is done to increase reliability in case either GEM or the remote endpoint crashes. If GEM crashes, it reads from the WAL and continues to forward metrics to the configured backend from the last sent timestamp. If the remote endpoint crashes, GEM continues to retry requests until it is available again. If multiple rule groups have been configured to send to the same remote-write endpoint, GEM will use a common WAL for the metrics generated by those rule groups. The WAL is truncated at the time specified by the `ruler.remote-write.wal-truncate-frequency` setting. WAL entries older than time specified in the `ruler.remote-write.max-wal-time` setting are removed. WAL entries younger than `ruler.remote-write.min-wal-time` are not removed.

By default, the WAL is stored in the `wal` folder in the GEM binary working directory.

console ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```console
$ ls
enterprise-metrics-binary   wal/
```

The directory can be configured as shown:

YAML ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```yaml
ruler:
  remote_write:
    enabled: true
    wal_dir: /tmp/wal
    min_wal_time: 1h
    max_wal_time: 5h
    wal_truncate_frequency: 1h
```

#### Example

The following is a complete example of the above mentioned config options using a ruler with sharding enabled and S3 as its rule storage backend:

YAML ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```yaml
ruler:
  external_url: localhost:9090
  rule_path: "/tmp/rules"
  storage:
    type: s3
    s3:
      endpoint: minio:9000
      access_key_id: cortex
      secret_access_key: supersecret
      bucketnames: "gem-ruler"
      insecure: true
      s3forcepathstyle: true
  poll_interval: 10s
  enable_api: true
  enable_sharding: true
  ring:
    kvstore:
      store: memberlist
  remote_write:
    enabled: true
    wal_dir: /tmp/wal
    min_wal_time: 1h
    max_wal_time: 5h
    wal_truncate_frequency: 1h
```

### Loading remote-write groups

The `mimirtool` tool is compatible with Prometheus rule files that contain the remote-write rule group syntax. You can download and use the latest version of the `mimirtool` [in the releases of Grafana Mimir](https://github.com/grafana/mimir/releases).

You can also use the docker image of the `mimirtool`: `docker pull grafana/mimirtool:latest`

#### Example usage

Once you have GEM running with remote-write rule groups enabled you can load remote-write rule groups using the following procedure.

1. Save the following file to your workspace:
   
   **rules.yaml:**

YAML ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```yaml
groups:
  - name: remote_write_group
    interval: 5m
    rules:
      - expr: "sum(up)"
        record: "sum_up"
    remote_write:
      - url: "http://user:pass@example.com/api/v1/push"
```

1. Run the following command with `mimirtool`:

Bash ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```bash
mimirtool rules sync \
--rule-files=rules.yaml \
--id=<tenant-name> \
--address=<gem-url> \
--key=<valid-gem-write-token>
```