Traefik Proxy¶

New

Introduced in 0.28.0

Dokku provides integration with the Traefik proxy service by utilizing the Docker label-based integration implemented by Traefik.

traefik:report [<app>] [<flag>]          # Displays a traefik report for one or more apps
traefik:logs [--num num] [--tail]        # Display traefik log output
traefik:set <app> <property> (<value>)   # Set or clear an traefik property for an app
traefik:show-config <app>                # Display traefik compose config
traefik:start                            # Starts the traefik server
traefik:stop                             # Stops the traefik server

Requirements¶

Using the traefik plugin integration requires the docker-compose-plugin for Docker. See this document from the Docker documentation for more information on the installation process for the docker-compose-plugin.

Usage¶

Warning

As using multiple proxy plugins on a single Dokku installation can lead to issues routing requests to apps, doing so should be avoided. As the default proxy implementation is nginx, users are encouraged to stop the nginx service before switching to Traefik.

The Traefik plugin has specific rules for routing requests:

Traefik integration is exposed via docker labels attached to containers. Changes in labels require either app deploys or rebuilds.
While Traefik will respect labels associated with other containers, only web containers have Traefik labels injected by the plugin.
Only http:80 and https:443 port mappings are supported.
If no http:80 mapping is found, the first http port mapping is used for http requests.
If no https:443 mapping is found, the first https port mapping is used for https requests.
If no https mapping is found, the container port from http:80 will be used for https requests.
Requests are routed as soon as the container is running and passing healthchecks.

Switching to Traefik¶

To use the Traefik plugin, use the proxy:set command for the app in question:

dokku proxy:set node-js-app traefik

This will enable the docker label-based Traefik integration. All future deploys will inject the correct labels for Traefik to read and route requests to containers. Due to the docker label-based integration used by Traefik, a single deploy or rebuild will be required before requests will route successfully.

dokku ps:rebuild node-js-app

Any changes to domains or port mappings will also require either a deploy or rebuild.

Starting Traefik container¶

Traefik can be started via the traefik:start command. This will start a Traefik container via the docker compose up command.

dokku traefik:start

Stopping the Traefik container¶

Traefik may be stopped via the traefik:stop command.

dokku traefik:stop

The Traefik container will be stopped and removed from the system. If the container is not running, this command will do nothing.

Showing the Traefik compose config¶

For debugging purposes, it may be useful to show the Traefik compose config. This can be achieved via the traefik:show-config command.

dokku traefik:show-config

Customizing the Traefik container image¶

While the default Traefik image is hardcoded, users may specify an alternative by setting the image property with the --global flag:

dokku traefik:set --global image traefik:v2.8

Checking the Traefik container's logs¶

It may be necessary to check the Traefik container's logs to ensure that Traefik is operating as expected. This can be performed with the traefik:logs command.

dokku traefik:logs

This command also supports the following modifiers:

--num NUM        # the number of lines to display
--tail           # continually stream logs

You can use these modifiers as follows:

dokku traefik:logs --tail --num 10

The above command will show logs continually from the traefik container, with an initial history of 10 log lines

Changing the Traefik log level¶

Traefik log output is set to ERROR by default. It may be changed by setting the log-level property with the --global flag:

dokku traefik:set --global log-level DEBUG

After modifying, the Traefik container will need to be restarted.

Setting rule priority¶

By default, app deployments will result in the newer traefik rules using a higher priority in order to have any newer rules respected by Traefik. Rule priorities will always increase according to the current unix timestamp. The priority may be fixed by setting the app-level priority property:

dokku traefik:set node-js-app priority 12345

After modifying, the app container will need to be recreated via a ps:rebuild or an app deployment.

SSL Configuration¶

The traefik plugin only supports automatic ssl certificates from it's letsencrypt integration. Managed certificates provided by the certs plugin are ignored.

Enabling letsencrypt integration¶

By default, letsencrypt is disabled and https port mappings are ignored. To enable, set the letsencrypt-email property with the --global flag:

dokku traefik:set --global letsencrypt-email automated@dokku.sh

After enabling, apps will need to be rebuilt and the Traefik container will need to be restarted. All http requests will then be redirected to https.

Customizing the letsencrypt server¶

The letsencrypt integration is set to the production letsencrypt server by default. To change this, set the letsencrypt-server property with the --global flag:

dokku traefik:set --global letsencrypt-server https://acme-staging-v02.api.letsencrypt.org/directory

After enabling, the Traefik container will need to be restarted and apps will need to be rebuilt to retrieve certificates from the new server.

API Access¶

Traefik exposes an API and Dashboard, which Dokku disables by default for security reasons. It can be exposed and customized as described below.

Enabling the api¶

Warning

Users enabling the dashboard should also enable api basic auth.

By default, the api is disabled. To enable, set the api property with the --global flag:

dokku traefik:set --global api true

After enabling, the Traefik container will need to be restarted.

Enabling the dashboard¶

Warning

Users enabling the dashboard should also enable api basic auth.

By default, the dashboard is disabled. To enable, set the dashboard property with the --global flag:

dokku traefik:set --global dashboard true

After enabling, the Traefik container will need to be restarted.

Enabling api basic auth¶

Users enabling either the api or dashboard are encouraged to enable basic auth. This will apply only to the api/dashboard, and not to apps. To enable, set the basic-auth-username and basic-auth-password properties with the --global flag:. Both must be set or basic auth will not be enabled.

dokku traefik:set --global basic-auth-username username
dokku traefik:set --global basic-auth-password password

After enabling, the Traefik container will need to be restarted.

Customizing the api hostname¶

The hostname used for the api and dashboard is set to traefik.dokku.me by default. It can be customized by setting the api-vhost property with the --global flag:

dokku traefik:set --global api-vhost lb.dokku.me

After enabling, the Traefik container will need to be restarted.

Displaying Traefik reports for an app¶

You can get a report about the app's Traefik config using the traefik:report command:

ShellOutput

dokku traefik:report

=====> node-js-app traefik information
       Traefik api enabled:           false
       Traefik api vhost:             traefik.dokku.me
       Traefik basic auth password:   password
       Traefik basic auth username:   user
       Traefik dashboard enabled:     false
       Traefik image:                 traefik:v2.8
       Traefik letsencrypt email:
       Traefik letsencrypt server:
       Traefik log level:             ERROR
=====> python-app traefik information
       Traefik api enabled:           false
       Traefik api vhost:             traefik.dokku.me
       Traefik basic auth password:   password
       Traefik basic auth username:   user
       Traefik dashboard enabled:     false
       Traefik image:                 traefik:v2.8
       Traefik letsencrypt email:
       Traefik letsencrypt server:
       Traefik log level:             ERROR
=====> ruby-app traefik information
       Traefik api enabled:           false
       Traefik api vhost:             traefik.dokku.me
       Traefik basic auth password:   password
       Traefik basic auth username:   user
       Traefik dashboard enabled:     false
       Traefik image:                 traefik:v2.8
       Traefik letsencrypt email:
       Traefik letsencrypt server:
       Traefik log level:             ERROR

You can run the command for a specific app also.

ShellOutput

dokku traefik:report node-js-app

=====> node-js-app traefik information
       Traefik api enabled:           false
       Traefik api vhost:             traefik.dokku.me
       Traefik basic auth password:   password
       Traefik basic auth username:   user
       Traefik dashboard enabled:     false
       Traefik image:                 traefik:v2.8
       Traefik letsencrypt email:
       Traefik letsencrypt server:
       Traefik log level:             ERROR

You can pass flags which will output only the value of the specific information you want. For example:

dokku traefik:report node-js-app --traefik-api-enabled