# Chain

When One Isn't Enough
{: .subtitle }

![Chain](../assets/img/middleware/chain.png)

The Chain middleware enables you to define reusable combinations of other pieces of middleware. 
It makes reusing the same groups easier.

## Configuration Example

Example "A Chain for WhiteList, BasicAuth, and HTTPS"

```yaml tab="Docker"
labels:
  - "traefik.http.routers.router1.service=service1"
  - "traefik.http.routers.router1.middlewares=secured"
  - "traefik.http.routers.router1.rule=Host(`mydomain`)"
  - "traefik.http.middlewares.secured.chain.middlewares=https-only,known-ips,auth-users"
  - "traefik.http.middlewares.auth-users.basicauth.users=test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/"
  - "traefik.http.middlewares.https-only.redirectscheme.scheme=https"
  - "traefik.http.middlewares.known-ips.ipwhitelist.sourceRange=192.168.1.7,127.0.0.1/32"
  - "http.services.service1.loadbalancer.server.port=80"
```

```yaml tab="Kubernetes"
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
  name: test
  namespace: default

spec:
  entryPoints:
    - web

  routes:
    - match: Host(`mydomain`)
      kind: Rule
      services:
        - name: whoami
          port: 80
      middlewares:
        - name: secured
---
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: secured
spec:
  chain:
    middlewares:
    - name: https-only
    - name: known-ips
    - name: auth-users
---
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: auth-users
spec:
  basicAuth:
    users:
    - test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/
---
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: https-only
spec:
  redirectScheme:
    scheme: https
---
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: known-ips
spec:
  ipWhiteList:
    sourceRange:
    - 192.168.1.7
    - 127.0.0.1/32
```

```json tab="Marathon"
"labels": {
  "traefik.http.routers.router1.service": "service1",
  "traefik.http.routers.router1.middlewares": "secured",
  "traefik.http.routers.router1.rule": "Host(`mydomain`)",
  "traefik.http.middlewares.secured.chain.middlewares": "https-only,known-ips,auth-users",
  "traefik.http.middlewares.auth-users.basicauth.users": "test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/",
  "traefik.http.middlewares.https-only.redirectscheme.scheme": "https",
  "traefik.http.middlewares.known-ips.ipwhitelist.sourceRange": "192.168.1.7,127.0.0.1/32",
  "http.services.service1.loadbalancer.server.port": "80"
}
```

```yaml tab="Rancher"
labels:
  - "traefik.http.routers.router1.service=service1"
  - "traefik.http.routers.router1.middlewares=secured"
  - "traefik.http.routers.router1.rule=Host(`mydomain`)"
  - "traefik.http.middlewares.secured.chain.middlewares=https-only,known-ips,auth-users"
  - "traefik.http.middlewares.auth-users.basicauth.users=test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/"
  - "traefik.http.middlewares.https-only.redirectscheme.scheme=https"
  - "traefik.http.middlewares.known-ips.ipwhitelist.sourceRange=192.168.1.7,127.0.0.1/32"
  - "http.services.service1.loadbalancer.server.port=80"
```

```toml tab="File (TOML)"
# ...    
[http.routers]
  [http.routers.router1]
    service = "service1"
    middlewares = ["secured"]
    rule = "Host(`mydomain`)"

[http.middlewares]
  [http.middlewares.secured.chain]
    middlewares = ["https-only", "known-ips", "auth-users"]

  [http.middlewares.auth-users.basicAuth]
    users = ["test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/"]

  [http.middlewares.https-only.redirectScheme]
    scheme = "https"

  [http.middlewares.known-ips.ipWhiteList]
    sourceRange = ["192.168.1.7", "127.0.0.1/32"]

[http.services]
  [http.services.service1]
    [http.services.service1.loadBalancer]
      [[http.services.service1.loadBalancer.servers]]
        url = "http://127.0.0.1:80"
```

```yaml tab="File (YAML)"
# ...    
http:
  routers:
    router1:
      service: service1
      middlewares:
        - secured
      rule: "Host(`mydomain`)"

  middlewares:
    secured:
      chain:
        middlewares:
          - https-only
          - known-ips
          - auth-users

    auth-users:
      basicAuth:
        users:
          - "test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/"

    https-only:
      redirectScheme:
        scheme: https

    known-ips:
      ipWhiteList:
        sourceRange:
          - "192.168.1.7"
          - "127.0.0.1/32"

  services:
    service1:
      loadBalancer:
        servers:
          - url: "http://127.0.0.1:80"
```