Traefik custom error pages when using Docker labels

问题

Later versions of Traefik support custom error pages – the ability to send a request to a different back end if there is an error. Commonly, this is a 502 when the reverse proxy can't communicate with a an application server. This docs page explains how to do this with the file backend type, and this works well enough.

However, I'm trying to use the Docker backend. This docs page shows a prospective Docker configuration – though it's not clear what the <name> substitution is supposed to mean.

So, using Docker Compose, I've got a basic setup where I want to direct all HTTP 500-599 traffic to an alternate backend, called error. Here's what I've got in docker-compose.yml:

version: '2'
services:
  traefik:
    image: traefik
    ports:
      - "80:80"
      - "8080:8080"
    restart: always
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
      - ./acme:/etc/traefik/acme/
      - ./traefik.toml:/etc/traefik/traefik.toml
  hello:
    image: kitematic/hello-world-nginx
    ports: 
      - "80"
    labels:
      - traefik.backend=hello
      - traefik.port=801
      - traefik.frontend.rule=Host:localhost
      - traefik.enable=true
      - traefik.frontend.errors.network.status=["500-599"]
      - traefik.frontend.errors.network.backend="error"
      - traefik.frontend.errors.network.query="/500s.html"
  error:
    image: kitematic/hello-world-nginx
    ports: 
      - "80"
    volumes:
      - ./html:/website_files
    labels:
      - "traefik.backend=error"
      - "traefik.port=80"
      - "traefik.frontend.rule=Host:error.localhost"
      - "traefik.enable=true"

As you can see, I've got a deliberate mismatch on the hello container between its published port and the port that Traefik is looking for. This is to force a 502 Bad Gateway error.

My traefik.toml file looks like this:

# defaultEntryPoints must be at the top because it should not be in any table below
defaultEntryPoints = ["http"]
# [accessLog]
logLevel = "DEBUG"

[web]
# Port for the status page
address = ":8080"

# Entrypoints, http and https
[entryPoints]

[entryPoints.http]
address = ":80"

[docker]
endpoint = "unix:///var/run/docker.sock"
domain = "localhost"
watch = true
exposedbydefault = true
# swarmmode = true

But, a request to http://localhost still returns the generic Bad gateway message, rather than redirecting to the /500s.html served by the error container (which works fine by going directly to http://error.localhost/500s.html)

Thank you anyone for your help!

回答1:

Error pages with labels are not available in 1.5: https://docs.traefik.io/v1.5/configuration/backends/docker/#on-containers

The support come in 1.6: https://docs.traefik.io/v1.6/configuration/backends/docker/#on-containers

来源：https://stackoverflow.com/questions/49673352/traefik-custom-error-pages-when-using-docker-labels

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Docker

Traefik