# Retry

Retrying until it Succeeds
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The Retry middleware is in charge of reissuing a request a given number of times to a backend server if that server does not reply.
To be clear, as soon as the server answers, the middleware stops retrying, regardless of the response status.
The Retry middleware has an optional configuration for exponential backoff.

## Configuration Examples

```yaml tab="Docker"
# Retry to send request 4 times with exponential backoff
labels:
  - "traefik.http.middlewares.test-retry.retry.attempts=4"
  - "traefik.http.middlewares.test-retry.retry.initialinterval=100ms"
```

```yaml tab="Kubernetes"
# Retry to send request 4 times with exponential backoff
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: test-retry
spec:
  retry:
    attempts: 4
    initialInterval: 100ms
```

```yaml tab="Consul Catalog"
# Retry to send request 4 times with exponential backoff
- "traefik.http.middlewares.test-retry.retry.attempts=4"
- "traefik.http.middlewares.test-retry.retry.initialinterval=100ms"
```

```json tab="Marathon"
"labels": {
  "traefik.http.middlewares.test-retry.retry.attempts": "4",
  "traefik.http.middlewares.test-retry.retry.initialinterval": "100ms",
}
```

```yaml tab="Rancher"
# Retry to send request 4 times with exponential backoff
labels:
  - "traefik.http.middlewares.test-retry.retry.attempts=4"
  - "traefik.http.middlewares.test-retry.retry.initialinterval=100ms"
```

```toml tab="File (TOML)"
# Retry to send request 4 times
[http.middlewares]
  [http.middlewares.test-retry.retry]
    attempts = 4
    initialInterval = "100ms"
```

```yaml tab="File (YAML)"
# Retry to send request 4 times with exponential backoff
http:
  middlewares:
    test-retry:
      retry:
        attempts: 4
        initialInterval: 100ms
```

## Configuration Options

### `attempts`

_mandatory_

The `attempts` option defines how many times the request should be retried.

### `initialInterval`

The `initialInterval` option defines the first wait time in the exponential backoff series (provided in seconds or as a valid duration format, see [time.ParseDuration](https://golang.org/pkg/time/#ParseDuration)). The maximum interval is calculated as twice the `initialInterval`. If unspecified, requests will be retried immediately.