Enabling the file provider:

```yaml tab="Structured (YAML)"
providers:
  file:
    filename: /etc/traefik/dynamic.yml
```

```toml tab="Structured (TOML)"
[providers.file]
  filename = "/etc/traefik/dynamic.toml"
```

```bash tab="CLI"
--providers.file.filename=/etc/traefik/dynamic.yml
```

Declaring the dynamic HTTP configuration:

```yaml tab="Structured (YAML)"
http:
  routers:
    app:
      rule: Host(`example.com`)
      entryPoints:
        - websecure
      service: app
      tls: {}

  services:
    app:
      loadBalancer:
        servers:
          - url: http://127.0.0.1:8080
```

```toml tab="Structured (TOML)"
[http.routers.app]
  rule = "Host(`example.com`)"
  entryPoints = ["websecure"]
  service = "app"

  [http.routers.app.tls]

[http.services.app.loadBalancer]
  [[http.services.app.loadBalancer.servers]]
    url = "http://127.0.0.1:8080"
```

Define each router and explicitly attach it to the service that should handle matching requests.

```yaml tab="Structured (YAML)"
http:
  routers:
    app:
      rule: Host(`example-a.com`)
      service: app
    admin:
      rule: Host(`example-b.com`)
      service: admin

  services:
    app:
      loadBalancer:
        servers:
          - url: http://127.0.0.1:8000
    admin:
      loadBalancer:
        servers:
          - url: http://127.0.0.1:9000
```

```toml tab="Structured (TOML)"
[http.routers.app]
  rule = "Host(`example-a.com`)"
  service = "app"

[http.routers.admin]
  rule = "Host(`example-b.com`)"
  service = "admin"

[http.services.app.loadBalancer]
  [[http.services.app.loadBalancer.servers]]
    url = "http://127.0.0.1:8000"

[http.services.admin.loadBalancer]
  [[http.services.admin.loadBalancer.servers]]
    url = "http://127.0.0.1:9000"
```

Middlewares declared by the file provider can be used by routers from the file provider or by routers from other providers.
When another provider references them, use the `@file` provider suffix.

```yaml tab="Structured (YAML)"
http:
  routers:
    app:
      rule: Host(`secure.example.com`)
      entryPoints:
        - websecure
      middlewares:
        - secure-headers
      service: app
      tls:
        options: modern

  middlewares:
    secure-headers:
      headers:
        stsSeconds: 31536000
        forceSTSHeader: true

  services:
    app:
      loadBalancer:
        servers:
          - url: http://127.0.0.1:8080

tls:
  options:
    modern:
      minVersion: VersionTLS12
      sniStrict: true
```

```toml tab="Structured (TOML)"
[http.routers.app]
  rule = "Host(`secure.example.com`)"
  entryPoints = ["websecure"]
  middlewares = ["secure-headers"]
  service = "app"

  [http.routers.app.tls]
    options = "modern"

[http.middlewares.secure-headers.headers]
  stsSeconds = 31536000
  forceSTSHeader = true

[http.services.app.loadBalancer]
  [[http.services.app.loadBalancer.servers]]
    url = "http://127.0.0.1:8080"

[tls.options.modern]
  minVersion = "VersionTLS12"
  sniStrict = true
```

Configure the file provider with a directory when you want to split dynamic configuration across multiple files.

```yaml tab="Structured (YAML)"
providers:
  file:
    directory: /etc/traefik/dynamic
    watch: true
```

```toml tab="Structured (TOML)"
[providers.file]
  directory = "/etc/traefik/dynamic"
  watch = true
```

```bash tab="CLI"
--providers.file.directory=/etc/traefik/dynamic
--providers.file.watch=true
```

Example `/etc/traefik/dynamic/http.yml`:

```yaml
http:
  routers:
    app:
      rule: Host(`example.com`)
      service: app

  services:
    app:
      loadBalancer:
        servers:
          - url: http://127.0.0.1:8080
```

Example `/etc/traefik/dynamic/tls.yml`:

```yaml
tls:
  certificates:
    - certFile: /certs/example.crt
      keyFile: /certs/example.key
```

If you declare multiple middlewares with the same name but different parameters, the middleware fails to be declared.

If you declare multiple middlewares with the same name but different parameters, the middleware fails to be declared.

Go Templating only works with dedicated dynamic configuration files.
Templating does not work in the Traefik main static configuration file.

```yaml tab="YAML"
http:
  routers:
    {{range $i, $e := until 100 }}
    router{{ $e }}-{{ env "MY_ENV_VAR" }}:
      # ...
    {{end}}

  services:
    {{range $i, $e := until 100 }}
    application{{ $e }}:
      # ...
    {{end}}

tcp:
  routers:
    {{range $i, $e := until 100 }}
    router{{ $e }}:
      # ...
    {{end}}

  services:
    {{range $i, $e := until 100 }}
    service{{ $e }}:
      # ...
    {{end}}

tls:
  certificates:
  {{ range $i, $e := until 10 }}
  - certFile: "/etc/traefik/cert-{{ $e }}.pem"
    keyFile: "/etc/traefik/cert-{{ $e }}.key"
    stores:
    - "my-store-foo-{{ $e }}"
    - "my-store-bar-{{ $e }}"
  {{end}}
```

```toml tab="TOML"
# template-rules.toml
[http]

  [http.routers]
  {{ range $i, $e := until 100 }}
    [http.routers.router{{ $e }}-{{ env "MY_ENV_VAR" }}]
    # ...
  {{ end }}

  [http.services]
  {{ range $i, $e := until 100 }}
      [http.services.service{{ $e }}]
      # ...
  {{ end }}

[tcp]

  [tcp.routers]
  {{ range $i, $e := until 100 }}
    [tcp.routers.router{{ $e }}]
    # ...
  {{ end }}

  [tcp.services]
  {{ range $i, $e := until 100 }}
      [tcp.services.service{{ $e }}]
      # ...
  {{ end }}

{{ range $i, $e := until 10 }}
[[tls.certificates]]
  certFile = "/etc/traefik/cert-{{ $e }}.pem"
  keyFile = "/etc/traefik/cert-{{ $e }}.key"
  stores = ["my-store-foo-{{ $e }}", "my-store-bar-{{ $e }}"]
{{ end }}

[tls.options]
{{ range $i, $e := until 10 }}
  [tls.options.TLS{{ $e }}]
  # ...
{{ end }}
```