traefik/docs/configuration/backends/docker.md
Jean-Baptiste Doumenjou 8627256e74 Remove Deprecated Step 1
2018-07-31 19:28:03 +02:00

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# Docker Provider
Træfik can be configured to use Docker as a provider.
## Docker
```toml
################################################################
# Docker Provider
################################################################
# Enable Docker Provider.
[docker]
# Docker server endpoint. Can be a tcp or a unix socket endpoint.
#
# Required
#
endpoint = "unix:///var/run/docker.sock"
# Default domain used.
# Can be overridden by setting the "traefik.domain" label on a container.
#
# Required
#
domain = "docker.localhost"
# Enable watch docker changes.
#
# Optional
#
watch = true
# Override default configuration template.
# For advanced users :)
#
# Optional
#
# filename = "docker.tmpl"
# Override template version
# For advanced users :)
#
# Optional
# - "1": previous template version (must be used only with older custom templates, see "filename")
# - "2": current template version (must be used to force template version when "filename" is used)
#
# templateVersion = 2
# Expose containers by default in Traefik.
# If set to false, containers that don't have `traefik.enable=true` will be ignored.
#
# Optional
# Default: true
#
exposedByDefault = true
# Use the IP address from the binded port instead of the inner network one.
# For specific use-case :)
#
# Optional
# Default: false
#
usebindportip = true
# Use Swarm Mode services as data provider.
#
# Optional
# Default: false
#
swarmMode = false
# Define a default docker network to use for connections to all containers.
# Can be overridden by the traefik.docker.network label.
#
# Optional
#
network = "web"
# Enable docker TLS connection.
#
# Optional
#
# [docker.tls]
# ca = "/etc/ssl/ca.crt"
# cert = "/etc/ssl/docker.crt"
# key = "/etc/ssl/docker.key"
# insecureSkipVerify = true
```
To enable constraints see [provider-specific constraints section](/configuration/commons/#provider-specific).
## Docker Swarm Mode
```toml
################################################################
# Docker Swarm Mode Provider
################################################################
# Enable Docker Provider.
[docker]
# Docker server endpoint.
# Can be a tcp or a unix socket endpoint.
#
# Required
# Default: "unix:///var/run/docker.sock"
#
endpoint = "tcp://127.0.0.1:2375"
# Default domain used.
# Can be overridden by setting the "traefik.domain" label on a services.
#
# Optional
# Default: ""
#
domain = "docker.localhost"
# Enable watch docker changes.
#
# Optional
# Default: true
#
watch = true
# Use Docker Swarm Mode as data provider.
#
# Optional
# Default: false
#
swarmMode = true
# Define a default docker network to use for connections to all containers.
# Can be overridden by the traefik.docker.network label.
#
# Optional
#
network = "web"
# Override default configuration template.
# For advanced users :)
#
# Optional
#
# filename = "docker.tmpl"
# Override template version
# For advanced users :)
#
# Optional
# - "1": previous template version (must be used only with older custom templates, see "filename")
# - "2": current template version (must be used to force template version when "filename" is used)
#
# templateVersion = 2
# Expose services by default in Traefik.
#
# Optional
# Default: true
#
exposedByDefault = false
# Enable docker TLS connection.
#
# Optional
#
# [docker.tls]
# ca = "/etc/ssl/ca.crt"
# cert = "/etc/ssl/docker.crt"
# key = "/etc/ssl/docker.key"
# insecureSkipVerify = true
```
To enable constraints see [provider-specific constraints section](/configuration/commons/#provider-specific).
## Labels: overriding default behavior
### Using Docker with Swarm Mode
If you use a compose file with the Swarm mode, labels should be defined in the `deploy` part of your service.
This behavior is only enabled for docker-compose version 3+ ([Compose file reference](https://docs.docker.com/compose/compose-file/#labels-1)).
```yaml
version: "3"
services:
whoami:
deploy:
labels:
traefik.docker.network: traefik
```
### Using Docker Compose
If you are intending to use only Docker Compose commands (e.g. `docker-compose up --scale whoami=2 -d`), labels should be under your service, otherwise they will be ignored.
```yaml
version: "3"
services:
whoami:
labels:
traefik.docker.network: traefik
```
### On Containers
Labels can be used on containers to override default behavior.
| Label | Description |
|------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `traefik.docker.network` | Overrides the default docker network to use for connections to the container. [1] |
| `traefik.domain` | Sets the default domain for the frontend rules. |
| `traefik.enable=false` | Disables this container in Træfik. |
| `traefik.port=80` | Registers this port. Useful when the container exposes multiples ports. |
| `traefik.protocol=https` | Overrides the default `http` protocol |
| `traefik.weight=10` | Assigns this weight to the container |
| `traefik.backend=foo` | Gives the name `foo` to the generated backend for this container. |
| `traefik.backend.buffering.maxRequestBodyBytes=0` | See [buffering](/configuration/commons/#buffering) section. |
| `traefik.backend.buffering.maxResponseBodyBytes=0` | See [buffering](/configuration/commons/#buffering) section. |
| `traefik.backend.buffering.memRequestBodyBytes=0` | See [buffering](/configuration/commons/#buffering) section. |
| `traefik.backend.buffering.memResponseBodyBytes=0` | See [buffering](/configuration/commons/#buffering) section. |
| `traefik.backend.buffering.retryExpression=EXPR` | See [buffering](/configuration/commons/#buffering) section. |
| `traefik.backend.circuitbreaker.expression=EXPR` | Creates a [circuit breaker](/basics/#backends) to be used against the backend |
| `traefik.backend.healthcheck.path=/health` | Enables health check for the backend, hitting the container at `path`. |
| `traefik.backend.healthcheck.interval=1s` | Defines the health check interval. |
| `traefik.backend.healthcheck.port=8080` | Sets a different port for the health check. |
| `traefik.backend.healthcheck.scheme=http` | Overrides the server URL scheme. |
| `traefik.backend.healthcheck.hostname=foobar.com` | Defines the health check hostname. |
| `traefik.backend.healthcheck.headers=EXPR` | Defines the health check request headers <br>Format: <code>HEADER:value&vert;&vert;HEADER2:value2</code> |
| `traefik.backend.loadbalancer.method=drr` | Overrides the default `wrr` load balancer algorithm |
| `traefik.backend.loadbalancer.stickiness=true` | Enables backend sticky sessions |
| `traefik.backend.loadbalancer.stickiness.cookieName=NAME` | Sets the cookie name manually for sticky sessions |
| `traefik.backend.loadbalancer.swarm=true` | Uses Swarm's inbuilt load balancer (only relevant under Swarm Mode). |
| `traefik.backend.maxconn.amount=10` | Sets a maximum number of connections to the backend.<br>Must be used in conjunction with the below label to take effect. |
| `traefik.backend.maxconn.extractorfunc=client.ip` | Sets the function to be used against the request to determine what to limit maximum connections to the backend by.<br>Must be used in conjunction with the above label to take effect. |
| `traefik.frontend.auth.basic=EXPR` | Sets the basic authentication to this frontend in CSV format: `User:Hash,User:Hash` [2] (DEPRECATED). |
| `traefik.frontend.auth.basic.removeHeader=true` | If set to `true`, removes the `Authorization` header. |
| `traefik.frontend.auth.basic.users=EXPR` | Sets the basic authentication to this frontend in CSV format: `User:Hash,User:Hash` [2]. |
| `traefik.frontend.auth.basic.usersfile=/path/.htpasswd` | Sets the basic authentication with an external file; if users and usersFile are provided, both are merged, with external file contents having precedence. |
| `traefik.frontend.auth.digest.removeHeader=true` | If set to `true`, removes the `Authorization` header. |
| `traefik.frontend.auth.digest.users=EXPR` | Sets the digest authentication to this frontend in CSV format: `User:Realm:Hash,User:Realm:Hash`. |
| `traefik.frontend.auth.digest.usersfile=/path/.htdigest` | Sets the digest authentication with an external file; if users and usersFile are provided, both are merged, with external file contents having precedence. |
| `traefik.frontend.auth.forward.address=https://example.com`| Sets the URL of the authentication server. |
| `traefik.frontend.auth.forward.tls.ca=/path/ca.pem` | Sets the Certificate Authority (CA) for the TLS connection with the authentication server. |
| `traefik.frontend.auth.forward.tls.caOptional=true` | Checks the certificates if present but do not force to be signed by a specified Certificate Authority (CA). |
| `traefik.frontend.auth.forward.tls.cert=/path/server.pem` | Sets the Certificate for the TLS connection with the authentication server. |
| `traefik.frontend.auth.forward.tls.insecureSkipVerify=true`| If set to true invalid SSL certificates are accepted. |
| `traefik.frontend.auth.forward.tls.key=/path/server.key` | Sets the Certificate for the TLS connection with the authentication server. |
| `traefik.frontend.auth.forward.trustForwardHeader=true` | Trusts X-Forwarded-* headers. |
| `traefik.frontend.auth.headerField=X-WebAuth-User` | Sets the header user to pass the authenticated user to the application. |
| `traefik.frontend.entryPoints=http,https` | Assigns this frontend to entry points `http` and `https`.<br>Overrides `defaultEntryPoints` |
| `traefik.frontend.errors.<name>.backend=NAME` | See [custom error pages](/configuration/commons/#custom-error-pages) section. |
| `traefik.frontend.errors.<name>.query=PATH` | See [custom error pages](/configuration/commons/#custom-error-pages) section. |
| `traefik.frontend.errors.<name>.status=RANGE` | See [custom error pages](/configuration/commons/#custom-error-pages) section. |
| `traefik.frontend.passHostHeader=true` | Forwards client `Host` header to the backend. |
| `traefik.frontend.passTLSCert=true` | Forwards TLS Client certificates to the backend. |
| `traefik.frontend.priority=10` | Overrides default frontend priority |
| `traefik.frontend.rateLimit.extractorFunc=EXP` | See [rate limiting](/configuration/commons/#rate-limiting) section. |
| `traefik.frontend.rateLimit.rateSet.<name>.period=6` | See [rate limiting](/configuration/commons/#rate-limiting) section. |
| `traefik.frontend.rateLimit.rateSet.<name>.average=6` | See [rate limiting](/configuration/commons/#rate-limiting) section. |
| `traefik.frontend.rateLimit.rateSet.<name>.burst=6` | See [rate limiting](/configuration/commons/#rate-limiting) section. |
| `traefik.frontend.redirect.entryPoint=https` | Enables Redirect to another entryPoint to this frontend (e.g. HTTPS) |
| `traefik.frontend.redirect.regex=^http://localhost/(.*)` | Redirects to another URL to this frontend.<br>Must be set with `traefik.frontend.redirect.replacement`. |
| `traefik.frontend.redirect.replacement=http://mydomain/$1` | Redirects to another URL to this frontend.<br>Must be set with `traefik.frontend.redirect.regex`. |
| `traefik.frontend.redirect.permanent=true` | Returns 301 instead of 302. |
| `traefik.frontend.rule=EXPR` | Overrides the default frontend rule. Default: `Host:{containerName}.{domain}` or `Host:{service}.{project_name}.{domain}` if you are using `docker-compose`. |
| `traefik.frontend.whiteList.sourceRange=RANGE` | Sets a list of IP-Ranges which are allowed to access.<br>An unset or empty list allows all Source-IPs to access.<br>If one of the Net-Specifications are invalid, the whole list is invalid and allows all Source-IPs to access. |
| `traefik.frontend.whiteList.useXForwardedFor=true` | Uses `X-Forwarded-For` header as valid source of IP for the white list. |
[1] `traefik.docker.network`:
If a container is linked to several networks, be sure to set the proper network name (you can check with `docker inspect <container_id>`) otherwise it will randomly pick one (depending on how docker is returning them).
For instance when deploying docker `stack` from compose files, the compose defined networks will be prefixed with the `stack` name.
Or if your service references external network use it's name instead.
[2] `traefik.frontend.auth.basic.users=EXPR `:
To create `user:password` pair, it's possible to use this command:
`echo $(htpasswd -nb user password) | sed -e s/\\$/\\$\\$/g`.
The result will be `user:$$apr1$$9Cv/OMGj$$ZomWQzuQbL.3TRCS81A1g/`, note additional symbol `$` makes escaping.
#### Custom Headers
| Label | Description |
|-------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `traefik.frontend.headers.customRequestHeaders=EXPR ` | Provides the container with custom request headers that will be appended to each request forwarded to the container.<br>Format: <code>HEADER:value&vert;&vert;HEADER2:value2</code> |
| `traefik.frontend.headers.customResponseHeaders=EXPR` | Appends the headers to each response returned by the container, before forwarding the response to the client.<br>Format: <code>HEADER:value&vert;&vert;HEADER2:value2</code> |
#### Security Headers
| Label | Description |
|----------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `traefik.frontend.headers.allowedHosts=EXPR` | Provides a list of allowed hosts that requests will be processed.<br>Format: `Host1,Host2` |
| `traefik.frontend.headers.browserXSSFilter=true` | Adds the X-XSS-Protection header with the value `1; mode=block`. |
| `traefik.frontend.headers.contentSecurityPolicy=VALUE` | Adds CSP Header with the custom value. |
| `traefik.frontend.headers.contentTypeNosniff=true` | Adds the `X-Content-Type-Options` header with the value `nosniff`. |
| `traefik.frontend.headers.customBrowserXSSValue=VALUE` | Set custom value for X-XSS-Protection header. This overrides the BrowserXssFilter option. |
| `traefik.frontend.headers.customFrameOptionsValue=VALUE` | Overrides the `X-Frame-Options` header with the custom value. |
| `traefik.frontend.headers.forceSTSHeader=false` | Adds the STS header to non-SSL requests. |
| `traefik.frontend.headers.frameDeny=false` | Adds the `X-Frame-Options` header with the value of `DENY`. |
| `traefik.frontend.headers.hostsProxyHeaders=EXPR ` | Provides a list of headers that the proxied hostname may be stored.<br>Format: `HEADER1,HEADER2` |
| `traefik.frontend.headers.isDevelopment=false` | This will cause the `AllowedHosts`, `SSLRedirect`, and `STSSeconds`/`STSIncludeSubdomains` options to be ignored during development.<br>When deploying to production, be sure to set this to false. |
| `traefik.frontend.headers.publicKey=VALUE` | Adds pinned HTST public key header. |
| `traefik.frontend.headers.referrerPolicy=VALUE` | Adds referrer policy header. |
| `traefik.frontend.headers.SSLRedirect=true` | Forces the frontend to redirect to SSL if a non-SSL request is sent. |
| `traefik.frontend.headers.SSLTemporaryRedirect=true` | Forces the frontend to redirect to SSL if a non-SSL request is sent, but by sending a 302 instead of a 301. |
| `traefik.frontend.headers.SSLHost=HOST` | This setting configures the hostname that redirects will be based on. Default is "", which is the same host as the request. |
| `traefik.frontend.headers.SSLForceHost=true` | If `SSLForceHost` is `true` and `SSLHost` is set, requests will be forced to use `SSLHost` even the ones that are already using SSL. Default is false. |
| `traefik.frontend.headers.SSLProxyHeaders=EXPR` | Header combinations that would signify a proper SSL Request (Such as `X-Forwarded-For:https`).<br>Format: <code>HEADER:value&vert;&vert;HEADER2:value2</code> |
| `traefik.frontend.headers.STSSeconds=315360000` | Sets the max-age of the STS header. |
| `traefik.frontend.headers.STSIncludeSubdomains=true` | Adds the `IncludeSubdomains` section of the STS header. |
| `traefik.frontend.headers.STSPreload=true` | Adds the preload flag to the STS header. |
### On containers with Multiple Ports (segment labels)
Segment labels are used to define routes to a container exposing multiple ports.
A segment is a group of labels that apply to a port exposed by a container.
You can define as many segments as ports exposed in a container.
Segment labels override the default behavior.
| Label | Description |
|---------------------------------------------------------------------------|---------------------------------------------------------------|
| `traefik.<segment_name>.backend=BACKEND` | Same as `traefik.backend` |
| `traefik.<segment_name>.domain=DOMAIN` | Same as `traefik.domain` |
| `traefik.<segment_name>.port=PORT` | Same as `traefik.port` |
| `traefik.<segment_name>.protocol=http` | Same as `traefik.protocol` |
| `traefik.<segment_name>.weight=10` | Same as `traefik.weight` |
| `traefik.<segment_name>.frontend.auth.basic=EXPR` | Same as `traefik.frontend.auth.basic` |
| `traefik.<segment_name>.frontend.auth.basic.removeHeader=true` | Same as `traefik.frontend.auth.basic.removeHeader` |
| `traefik.<segment_name>.frontend.auth.basic.users=EXPR` | Same as `traefik.frontend.auth.basic.users` |
| `traefik.<segment_name>.frontend.auth.basic.usersfile=/path/.htpasswd` | Same as `traefik.frontend.auth.basic.usersfile` |
| `traefik.<segment_name>.frontend.auth.digest.removeHeader=true` | Same as `traefik.frontend.auth.digest.removeHeader` |
| `traefik.<segment_name>.frontend.auth.digest.users=EXPR` | Same as `traefik.frontend.auth.digest.users` |
| `traefik.<segment_name>.frontend.auth.digest.usersfile=/path/.htdigest` | Same as `traefik.frontend.auth.digest.usersfile` |
| `traefik.<segment_name>.frontend.auth.forward.address=https://example.com`| Same as `traefik.frontend.auth.forward.address` |
| `traefik.<segment_name>.frontend.auth.forward.tls.ca=/path/ca.pem` | Same as `traefik.frontend.auth.forward.tls.ca` |
| `traefik.<segment_name>.frontend.auth.forward.tls.caOptional=true` | Same as `traefik.frontend.auth.forward.tls.caOptional` |
| `traefik.<segment_name>.frontend.auth.forward.tls.cert=/path/server.pem` | Same as `traefik.frontend.auth.forward.tls.cert` |
| `traefik.<segment_name>.frontend.auth.forward.tls.insecureSkipVerify=true`| Same as `traefik.frontend.auth.forward.tls.insecureSkipVerify`|
| `traefik.<segment_name>.frontend.auth.forward.tls.key=/path/server.key` | Same as `traefik.frontend.auth.forward.tls.key` |
| `traefik.<segment_name>.frontend.auth.forward.trustForwardHeader=true` | Same as `traefik.frontend.auth.forward.trustForwardHeader` |
| `traefik.<segment_name>.frontend.auth.headerField=X-WebAuth-User` | Same as `traefik.frontend.auth.headerField` |
| `traefik.<segment_name>.frontend.entryPoints=https` | Same as `traefik.frontend.entryPoints` |
| `traefik.<segment_name>.frontend.errors.<name>.backend=NAME` | Same as `traefik.frontend.errors.<name>.backend` |
| `traefik.<segment_name>.frontend.errors.<name>.query=PATH` | Same as `traefik.frontend.errors.<name>.query` |
| `traefik.<segment_name>.frontend.errors.<name>.status=RANGE` | Same as `traefik.frontend.errors.<name>.status` |
| `traefik.<segment_name>.frontend.passHostHeader=true` | Same as `traefik.frontend.passHostHeader` |
| `traefik.<segment_name>.frontend.passTLSCert=true` | Same as `traefik.frontend.passTLSCert` |
| `traefik.<segment_name>.frontend.priority=10` | Same as `traefik.frontend.priority` |
| `traefik.<segment_name>.frontend.rateLimit.extractorFunc=EXP` | Same as `traefik.frontend.rateLimit.extractorFunc` |
| `traefik.<segment_name>.frontend.rateLimit.rateSet.<name>.period=6` | Same as `traefik.frontend.rateLimit.rateSet.<name>.period` |
| `traefik.<segment_name>.frontend.rateLimit.rateSet.<name>.average=6` | Same as `traefik.frontend.rateLimit.rateSet.<name>.average` |
| `traefik.<segment_name>.frontend.rateLimit.rateSet.<name>.burst=6` | Same as `traefik.frontend.rateLimit.rateSet.<name>.burst` |
| `traefik.<segment_name>.frontend.redirect.entryPoint=https` | Same as `traefik.frontend.redirect.entryPoint` |
| `traefik.<segment_name>.frontend.redirect.regex=^http://localhost/(.*)` | Same as `traefik.frontend.redirect.regex` |
| `traefik.<segment_name>.frontend.redirect.replacement=http://mydomain/$1` | Same as `traefik.frontend.redirect.replacement` |
| `traefik.<segment_name>.frontend.redirect.permanent=true` | Same as `traefik.frontend.redirect.permanent` |
| `traefik.<segment_name>.frontend.rule=EXP` | Same as `traefik.frontend.rule` |
| `traefik.<segment_name>.frontend.whiteList.sourceRange=RANGE` | Same as `traefik.frontend.whiteList.sourceRange` |
| `traefik.<segment_name>.frontend.whiteList.useXForwardedFor=true` | Same as `traefik.frontend.whiteList.useXForwardedFor` |
#### Custom Headers
| Label | Description |
|----------------------------------------------------------------------|----------------------------------------------------------|
| `traefik.<segment_name>.frontend.headers.customRequestHeaders=EXPR ` | Same as `traefik.frontend.headers.customRequestHeaders` |
| `traefik.<segment_name>.frontend.headers.customResponseHeaders=EXPR` | Same as `traefik.frontend.headers.customResponseHeaders` |
#### Security Headers
| Label | Description |
|-------------------------------------------------------------------------|--------------------------------------------------------------|
| `traefik.<segment_name>.frontend.headers.allowedHosts=EXPR` | Same as `traefik.frontend.headers.allowedHosts` |
| `traefik.<segment_name>.frontend.headers.browserXSSFilter=true` | Same as `traefik.frontend.headers.browserXSSFilter` |
| `traefik.<segment_name>.frontend.headers.contentSecurityPolicy=VALUE` | Same as `traefik.frontend.headers.contentSecurityPolicy` |
| `traefik.<segment_name>.frontend.headers.contentTypeNosniff=true` | Same as `traefik.frontend.headers.contentTypeNosniff` |
| `traefik.<segment_name>.frontend.headers.customBrowserXSSValue=VALUE` | Same as `traefik.frontend.headers.customBrowserXSSValue` |
| `traefik.<segment_name>.frontend.headers.customFrameOptionsValue=VALUE` | Same as `traefik.frontend.headers.customFrameOptionsValue` |
| `traefik.<segment_name>.frontend.headers.forceSTSHeader=false` | Same as `traefik.frontend.headers.forceSTSHeader` |
| `traefik.<segment_name>.frontend.headers.frameDeny=false` | Same as `traefik.frontend.headers.frameDeny` |
| `traefik.<segment_name>.frontend.headers.hostsProxyHeaders=EXPR` | Same as `traefik.frontend.headers.hostsProxyHeaders` |
| `traefik.<segment_name>.frontend.headers.isDevelopment=false` | Same as `traefik.frontend.headers.isDevelopment` |
| `traefik.<segment_name>.frontend.headers.publicKey=VALUE` | Same as `traefik.frontend.headers.publicKey` |
| `traefik.<segment_name>.frontend.headers.referrerPolicy=VALUE` | Same as `traefik.frontend.headers.referrerPolicy` |
| `traefik.<segment_name>.frontend.headers.SSLRedirect=true` | Same as `traefik.frontend.headers.SSLRedirect` |
| `traefik.<segment_name>.frontend.headers.SSLTemporaryRedirect=true` | Same as `traefik.frontend.headers.SSLTemporaryRedirect` |
| `traefik.<segment_name>.frontend.headers.SSLHost=HOST` | Same as `traefik.frontend.headers.SSLHost` |
| `traefik.<segment_name>.frontend.headers.SSLForceHost=true` | Same as `traefik.frontend.headers.SSLForceHost` |
| `traefik.<segment_name>.frontend.headers.SSLProxyHeaders=EXPR` | Same as `traefik.frontend.headers.SSLProxyHeaders=EXPR` |
| `traefik.<segment_name>.frontend.headers.STSSeconds=315360000` | Same as `traefik.frontend.headers.STSSeconds=315360000` |
| `traefik.<segment_name>.frontend.headers.STSIncludeSubdomains=true` | Same as `traefik.frontend.headers.STSIncludeSubdomains=true` |
| `traefik.<segment_name>.frontend.headers.STSPreload=true` | Same as `traefik.frontend.headers.STSPreload=true` |
!!! note
If a label is defined both as a `container label` and a `segment label` (for example `traefik.<segment_name>.port=PORT` and `traefik.port=PORT` ), the `segment label` is used to defined the `<segment_name>` property (`port` in the example).
It's possible to mix `container labels` and `segment labels`, in this case `container labels` are used as default value for missing `segment labels` but no frontends are going to be created with the `container labels`.
More details in this [example](/user-guide/docker-and-lets-encrypt/#labels).
!!! warning
When running inside a container, Træfik will need network access through:
`docker network connect <network> <traefik-container>`