Port forwarding with traefik and docker-compose - docker-compose

I would like to serve a docker-compose service through traefik with port-forwarding. I had many tries and the best I could achieve from now is described below:
First I create two networks:
docker network create frontend # To expose traefik
docker network create backend # To bind backend services
The traefik configuration is about (development, dashboard enabled at :8080):
version: "3.6"
services:
proxy:
image: traefik:latest
restart: unless-stopped
command:
- "--log.level=DEBUG"
- "--api"
- "--api.dashboard"
- "--api.insecure"
- "--providers.docker"
- "--providers.docker.exposedbydefault=false"
# Service entrypoint:
- "--entrypoints.lora-server.address=:8090"
volumes:
- "/var/run/docker.sock:/var/run/docker.sock:ro"
labels:
- "traefik.enable=true"
- "traefik.docker.network=frontend"
- "traefik.http.routers.traefik.entrypoints=traefik"
- "traefik.http.routers.traefik.service=api#internal"
networks:
- backend
- frontend
ports:
- "8080:8080"
- "8090:8090"
networks:
frontend:
external: true
backend:
external: true
The backend service is described here (a fork from ChripStack but it could be anything else):
version: "3"
services:
# [...]
chirpstack-application-server:
image: chirpstack/chirpstack-application-server:3
networks:
- backend
volumes:
- ./configuration/chirpstack-application-server:/etc/chirpstack-application-server
labels:
- "traefik.enable=true"
- "traefik.docker.network=backend"
- "traefik.http.routers.chirpstack.entrypoints=lora-server"
- "traefik.http.routers.chirpstack.rule=Host(`{host:}`)"
- "traefik.http.routers.chirpstack.service=chirpstack-application-server#docker"
- "traefik.http.services.chirpstack-application-server.loadbalancer.server.port=8080"
# [...]
networks:
backend:
external: true
The service also natively run on :8080 and I would like to access it on :8090 through traefik.
When I run both applications, traefik registers the new service and does not complain (no errors, no warning, the flow seems complete at least from the dashboard interface).
time="2020-07-30T11:47:47Z" level=debug msg="Creating middleware" middlewareType=Pipelining serviceName=chirpstack-application-server#docker entryPointName=lora-server routerName=chirpstack#docker middlewareName=pipelining
time="2020-07-30T11:47:47Z" level=debug msg="Creating load-balancer" entryPointName=lora-server routerName=chirpstack#docker serviceName=chirpstack-application-server#docker
time="2020-07-30T11:47:47Z" level=debug msg="Creating server 0 http://192.168.112.9:8080" entryPointName=lora-server routerName=chirpstack#docker serviceName=chirpstack-application-server#docker serverName=0
time="2020-07-30T11:47:47Z" level=debug msg="Added outgoing tracing middleware chirpstack-application-server#docker" middlewareName=tracing entryPointName=lora-server routerName=chirpstack#docker middlewareType=TracingForwarder
But I could not access the service, I am geting 404 errors when I try to connect http://host:8090.
To my understanding, it seems traefik does not know how it should complete the flow between the two networks: http://frontend:8090 -> http://backend:8080 (because I haven't referenced it anywhere).
What should I change in my configuration to make it work? How can I specify to traefik that it must route the HTTP traffic from frontend:8090 to backend:8080? Your help is much appreciated.

Traefik listens on some port, that's the only thing defined with entrypoints. You don't specify network for this incoming requests, because it's unrelated. traefik.docker.network is only used for routing after Traefik handles the incoming requests.
So the correct flow is not http://frontend:8090 -> http://backend:8080, but http://host:8090 -> http://backend:8080.
I think your configuration is correct. The only thing which seems to be odd is usage of Host rule. Maybe try to change it to something like this:
"traefik.http.routers.chirpstack.rule=hostregexp(`{host:.+}`)"

Related

Traefik with multiple docker-compose.yml files

Hello traefik friends.
I just started to look into traefik. All tutorials show how to run one docker-compose.yml file with traefik togather with other containers. I most often have many separate docker-compose.yml files and very much would like to use them with traefik.
so here is my code for traefik container:
version: "3.3"
services:
traefik:
image: "traefik:v2.5"
container_name: "traefik"
command:
#- "--log.level=DEBUG"
- "--api.insecure=true"
- "--providers.docker=true"
- "--providers.docker.exposedbydefault=false"
- "--entrypoints.websecure.address=:443"
- "--certificatesresolvers.myresolver.acme.tlschallenge=true"
#- "--certificatesresolvers.myresolver.acme.caserver=https://acme-staging-v02.api.letsencrypt.org/directory"
- "--certificatesresolvers.myresolver.acme.email=xxxxxxxxx#gmail.com"
- "--certificatesresolvers.myresolver.acme.storage=/letsencrypt/acme.json"
ports:
- "443:443"
- "8080:8080"
networks:
- "traefik"
- "external"
volumes:
- "./letsencrypt:/letsencrypt"
- "/var/run/docker.sock:/var/run/docker.sock:ro"
and the other exemplary docker-compose I would like to use with traefik:
version: '3.1'
services:
php:
image: php:7.4-apache
ports:
- 8081:80
volumes:
- ./php/www:/var/www/html/
labels:
- "traefik.enable=true"
- "traefik.http.routers.php.rule=host(`php.xxxxxx.com`)"
- "traefik.http.routers.php.entrypoints=websecure"
- "traefik.http.routers.php.tls.certresolver=myresolver"
unfortunately that doesnt seem to work (when I concat theese to files into one big docker-compose.yml file - it works fine. Could you point me in the right direction?
Traefik needs to be part of the networks for all the services it connects to. For me it works when I set network: host for Traefik. (And then you have to remove ports part.)
I do wonder how safe that is, I can't seem to access the admin interface from another machine, so that's good.
Each docker-compose.yml by default create its own network. So traefik from the traefik network can't access PHP server from some other "php-default" network.
see Compose Networking docs
We have to add the PHP server to the traefik network:
php/docker-compose.yml:
services:
php:
image: php:7.4-apache
# we need to tell the traefik what port is the container listening to
expose:
- 80
volumes:
- ./php/www:/var/www/html/
labels:
- "traefik.enable=true"
- "traefik.http.routers.php.rule=host(`php.xxxxxx.com`)"
- "traefik.http.routers.php.entrypoints=websecure"
- "traefik.http.routers.php.tls.certresolver=myresolver"
networks:
default:
name: traefik
external: true
OR if you want to have other networks
services:
php:
...
networks:
- traefik
...
networks:
traefik:
external: true
Note there is not defined port property, instead there is expose. The port exposes ports on the host, the expose act as mere documentation (see this Q) but the traefik read it.
And because of that, I think that in your traefik/docker-compose.yml the external network is unnecessary.

Port forwarding problem using Traefik and docker-compose

I want the next port forwarding:
http://traefik.service.localhost/ -> Traefik UI
http://api.service.localhost/ -> 'Hello-Word' page from api-service
Here is my attempt to create appropriate docker-compose.yml file:
version: '3.8'
services:
reverse-proxy:
image: traefik:v2.4
container_name: reverse-proxy
command:
- "--api.insecure=true"
- "--providers.docker"
ports:
- "80:80"
- "8080:8080"
labels:
- traefik.enable=true
- traefik.docker.network=pred-network
volumes:
- /var/run/docker.sock:/var/run/docker.sock
networks:
- pred-network
api-service:
image: x86_64/prediction-service:0.8.1
container_name: api-service
environment:
SERVING_SERVICE: model-service
expose:
- 80
labels:
- traefik.enable=true
- traefik.http.routers.api-service.rule=Host(`api.service.localhost`)
networks:
- pred-network
networks:
pred-network:
I am getting the following:
http://traefik.service.localhost/ -> HTTP Error 404. The requested resource is not found.
http://api.service.localhost/ -> HTTP Error 404. The requested resource is not found.
The only link that actually works:
http://api.service.localhost:8080/ -> Traefik UI
If I would include:
ports:
- "8070:80"
into api-service part of docker-compose.yml I could access my 'Hello-Word':
http://localhost:8070/ -> "Hello-Word"
In this case it not get routed through Traefik but directly through api-service. Is it possible to do it over Traefik?
To have a service routed by traefik with docker, you should have labels. Traefik will fetch those labels in order to know how to do routing.
Thus, to have request of api.service.localhost routed to your api service, you should have the label that define the corresponding rule:
traefik.http.routers.service.rule=Host(`api.service.localhost`)
As for the label of Traefik, you should have two labels:
traefik.http.routers.traefik.rule=Host(`traefik.service.localhost`)
traefik.http.routers.traefik.service=api#internal
Beside those traefik labels, you should tell traefik to expose the dashboard using a specific service by adding this configuration: --api.dashboard (More help to expose the dashboard here).
Note, if your api service uses another port than the one by default, you could add this label:
traefik.http.services.service.loadbalancer.server.port=80
Ps, do not expose twice the port 80, you only need to expose it for the traefik container.

Bad Gateway with Traefik and Docker Compose

I'm trying to deploy a React + FastApi + Postgres application on docker compose with Traefik as the reverse proxy. I'm running into issues with Bad Gateway errors. Running my FastAPI locally runs it on port 8888 and exposes the path /docs to view the api documentation. I'd like to eventually have the application running on example.local with the docs available on example.local/api/docs. My docker-compose.yaml is as follows (loosely based on this one):
version: '3.8'
services:
proxy:
image: traefik:v2.4
networks:
- web
volumes:
- /var/run/docker.sock:/var/run/docker.sock
ports:
- '80:80'
- '8080:8080'
- '443:443'
command:
- --providers.docker
- --api.insecure=true
- --providers.docker.exposedbydefault=false
- --providers.docker.network=web
- --entrypoints.web.address=:80
labels:
- traefik.enable=true
- traefik.http.routers.example-proxy-http.rule=Host(`example.local`)
- traefik.http.routers.example-proxy-http.entrypoints=web
- traefik.http.services.example-proxy.loadbalancer.server.port=80
backend:
build:
context: ./backend
dockerfile: Dockerfile
command: python app/main.py
volumes:
- ./backend/app:/app
env_file:
- .env
networks:
- web
- backend
labels:
- traefik.enable=true
- traefik.http.routers.example-backend-http.rule=PathPrefix(`api/docs`)
- traefik.http.routers.example-backend-http.entrypoints=web
- traefik.http.services.example-backend.loadbalancer.server.port=8888
networks:
web:
external: true
backend:
external: false
I've added 127.0.0.1 example.local to my /etc/hosts file.
From reading around it seems like Bad Gateway errors tend to occur from traefik and related services not being on the same network, or traefik routing traffic to the wrong port on the service container. However if I set ports: - '8888:8888' in my backend service I can access the docs from localhost:8888/docs so I'm pretty sure 8888 is the correct port for the backend loadbalancer. From what I can see traefik and the backend service are on the same network too and I've set it as the default traefik network with --providers.docker.network=web. Interestingly if I visit localhost/api/docs in my browser I'm served up a page from FastAPI. So it could be an issue with my traefik http router labels? I'm quite new to traefik and proxies so would appreciate any help or guidance, thanks!
UPDATE
If I specify the host for the backend by adding
- traefik.http.routers.infilmation-backend-http.rule=Host(`example.local`) && PathPrefix(`/docs`)
to the backend service labels, then visiting example.local/docs does serve up page from FastApi. So I guess my question would be what is the best way of setting up a host for this application? Is there a way I can specify a default host for all services then any PathPrefix rules would be in relation to that host?

Keycloak Gatekeeper (forwarding proxy) does nothing

I have a docker-compose setup with service 1 (grafana) sending requests to service 2 (prometheus).
I've put a Keycloak Gatekeeper in front of service 2, asking for authentication.
That works perfectly fine.
Now my idea was to also place a second Keycloak Gatekeeper in front of service 1, injecting said authentication.
Unfortunately, that doesnt work.
Observing my traffic via wireshark, it seems my second Keycloak Gatekeeper is not even involved in any communication.
My docker compose file for service 1 and the forwarding proxy looks roughly like this:
keycloak-forwarder:
image: quay.io/keycloak/keycloak-gatekeeper
command:
- --enable-forwarding=true
- --forwarding-username=<my_username>
- --forwarding-password=<my_password>
- --forwarding-domains=${BASE_DOMAIN}/grafana
- --listen=:3001
- --client-id=<my_keycloak_client_id>
- --client-secret=<my_keycloak_client_secret>
- --discovery-url=${DOMAIN_PROTOCOL}://${KEYCLOAK_DOMAIN}/auth/realms/<my_keycloak_realm>
networks:
- webgateway
grafana:
image: grafana/grafana
networks:
- webgateway
labels:
traefik.enable: true
traefik.backend: grafana
traefik.frontend.rule: Host:${BASE_DOMAIN};PathPrefix:/grafana;PathPrefixStrip:/grafana
traefik.port: 3000
traefik.docker.network: webgateway
Ok, I've found the solution.
There are several things, that I did wrong.
The forwarding-domains flag describes the domains the request goes to,
not comes from. So if grafana talks to prometheus, the prometheus
domain needs to be entered here.
The Keycloak Gatekeeper doesn't automatically intercept communication. So grafana
needs to use it explicitly as proxy.
So the fixed docker-compose looks the following:
keycloak-forwarder:
image: quay.io/keycloak/keycloak-gatekeeper
command:
- --enable-forwarding=true
- --forwarding-username=<my_username>
- --forwarding-password=<my_password>
- --forwarding-domains=${BASE_DOMAIN}/prometheus
- --listen=:3001
- --client-id=<my_keycloak_client_id>
- --client-secret=<my_keycloak_client_secret>
- --discovery-url=${DOMAIN_PROTOCOL}://${KEYCLOAK_DOMAIN}/auth/realms/<my_keycloak_realm>
networks:
- webgateway
grafana:
image: grafana/grafana
networks:
- webgateway
environment:
- HTTP_PROXY=http://keycloak-forwarder:3001
- HTTPS_PROXY=http://keycloak-forwarder:3001
labels:
traefik.enable: true
traefik.backend: grafana
traefik.frontend.rule: Host:${BASE_DOMAIN};PathPrefix:/grafana;PathPrefixStrip:/grafana
traefik.port: 3000
traefik.docker.network: webgateway

Debugging Traefik when the Site Cannot Be Reached from outside Company's Intranet

Using docker-compose I have deployed a web application that uses Traefik as the reverse proxy, listening on port 80. This works without problem when I'm inside my company's intranet. Outside of the intranet, however, I get a 'site cannot be reached' response. Pinging the address from outside shows that the address is reachable and port 80 is open.
I've also tried to use segments in my Traefik configuration to route both the internal and external hostname I have been provided but this has no effect:
version: "3.5"
services:
test:
image: emilevauge/whoami
deploy:
labels:
traefik.enable: "true"
traefik.foo.frontend.rule: "Host:${HOSTNAME};PathPrefixStrip:/test"
traefik.bar.frontend.rule: "Host:${EXTERNAL_HOSTNAME};PathPrefixStrip:/test"
traefik.port: 80
networks:
- frontend
...
I have configured the access logs to see if my requests are reaching Traefik, can anyone advise me what I should be looking for and how to filter the huge amount of text produced to find it? This is my Traefik setup configuration:
version: '3.5'
services:
traefik:
image: traefik:alpine
command: |-
--entryPoints="Name:http Address::80"
--entryPoints="Name:https Address::443 TLS"
--defaultentrypoints="http,https"
--acme
--acme.acmelogging="true"
--acme.domains="${HOSTNAME}"
--acme.domains="${EXTERNAL_HOSTNAME}"
--acme.email="${ACME_EMAIL}"
--acme.entrypoint="https"
--acme.httpchallenge
--acme.httpchallenge.entrypoint="http"
--acme.storage="/opt/traefik/acme.json"
--acme.onhostrule="true"
--docker
--docker.swarmmode
--docker.domain="${HOSTNAME}"
--docker.network="frontend"
--docker.watch
--api
--api.statistics
--logLevel="DEBUG"
networks:
- frontend