I've an installation with 2 backend services that should be proxied by a third Nginx service.
I've deployed the 3 services succesfully but for some reason I can't get nginx to see the other 2 services giving the error:
GET / HTTP/1.1" 502 560
and
[error] 8#8: *1 no live upstreams while connecting to upstream
I have tried changing all the services to their own network but it seems the issue is not solved.
Adding my docker-compose.yml:
version: "3"
services:
nginx_web_1:
image: nginx:1.17
volumes:
- "./files_1:/usr/share/nginx/html:ro"
nginx_web_2:
image: nginx:1.17
volumes:
- "./files_2:/usr/share/nginx/html:ro"
nginx_balancer:
build: ./balancer
ports:
- 5000:80
depends_on:
- nginx_web_1
- nginx_web_2
and this is how I configured the proxy:
File moved to /etc/nginx/conf.d/default.conf
upstream backend_hosts {
server nginx_web_1;
server nginx_web_2;
}
server {
listen 80;
server_name localhost;
location / {
proxy_pass http://backend_hosts;
}
}
After some investigation, the issue was that I was running only docker-compose up/down which didn't rebuild my Nginx proxy image.
After cleaning up and running a docker build the proxy was configured properly and now runs fine.
That means that also the config listed in the question is a valid one
Related
I have a FastAPI API that I want to serve using gunicorn, nginx and docker compose.
I manage to make the FastApi and Gunicorn work with docker compose, now I add nginx. But I cannot manage to make it work. When I do curl http://localhost:80 I get this messsage: If you see this page, the nginx web server is successfully installed and working. Further configuration is required.
So this is my docker compose file:
version: '3.8'
services:
web:
build:
dockerfile: Dockerfile.prod
context: .
command: gunicorn main:app --bind 0.0.0.0:8000 --worker-class uvicorn.workers.UvicornWorker
expose:
- 8000
env_file:
- ./.env.prod
nginx:
build:
dockerfile: Dockerfile.prod
context: ./nginx
ports:
- 1337:80
depends_on:
- web
On this one, if I set ports to 80:80 I get an error when the image is composed: Error starting userland proxy: listen tcp4 0.0.0.0:80: bind: address already in use, which I don't know why.
If I put [some random number]:80 (e.g. 1337:80) then the docker build works, but I get the If you see this page, the nginx web server is successfully installed but... error message state before. I think 1337 is not where nginx is listening, and that's why.
This is my nginx conf file:
upstream platic_service {
server web:8000;
}
server {
listen 80;
location / {
proxy_pass http://platic_service;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $host;
proxy_redirect off;
}
I tried to change it to listen to 8080 but does not work.
What am I doing wrong?
I'm trying to use nginx as a reverse proxy using the below docker-compose file
version: '3'
services:
nginx:
image: nginx
volumes:
- "nginx-conf:/etc/nginx/conf.d"
ports:
- 80:80
depends_on:
- nginxtest
nginxtest:
image: nginx
volumes:
nginx-conf:
Inside ${PWD}/nginx-conf I've the default.conf file like so
http {
server {
listen 80;
location / {
proxy_pass http://nginxtext;
}
}
}
nginx container doesn't load my reverse proxy config; instead it loads default config.
It depends what you are trying to achieve, as per documentation.
Those lines are of interest in this particular case:
# Path on the host, relative to the Compose file
- ./volume_name:/some/docker/path
# Named volume
- volume_name:/some/docker/path
If you are trying to mount folder from host, to nginx configuration folder, update the volumes part to the following:
volumes:
- "~/nginx-conf:/etc/nginx/conf.d"
I have a Flask app, which runs inside a Docker container and should be exposed under a specific URL: myserver.com/mylocation. I want to use another container running Nginx as a reverse proxy to achieve the routing. I am following an awesome tutorial that got me quite far already.
My Nginx-config (the relevant part) reads:
server {
server_name myserver.com;
location /mylocation {
proxy_pass http://myapp:5000;
proxy_set_header Host $host;
rewrite ^/mylocation(.*)$ $1 break;
}
}
My docker-compose.yml reads:
version: '2'
services:
nginx:
image: nginx:latest
container_name: production_nginx
volumes:
- ./nginx.conf:/etc/nginx/nginx.conf
ports:
- 80:80
- 443:443
myapp:
build: .
image: app_image
container_name: app_container
expose:
- "5000"
Now, when I run this, I successfully get my applications' index.html from myserver.com/mylocation, but subsequent requests (the CSS, JS etc) are being fired at myserver.com without the location part (/mylocation), and so Nginx does not route them to the container and they 404. The references to CSS, JS and such are all relative, they do not (and should not) contain the server name and location.
How can I achieve this? Am I missing something in my NGinx config that would let the app know it should run at /mylocation?
Short description:
Nginx running on docker, how to configure nginx so that it forwards calls to host.
Long description:
We have one web application which communicates to couple of backends (lets says rest1, rest2 and rest3). We are responsible for rest1.
Lets consider that I started rest1 manually on my pc and running on 2345 port. I want nginx (which is running in docker) to redirect all call torest1 to my own running instance(note, the instance is running on host, not any container and not in docker). And for rest2 and rest3 to some other docker node or may be some other server (who cares).
What I am looking for is:
docker-compose.yml configurations (if needed).
nginx configuration.
Thanks in advance.
Configure nginx like the following (make sure you replace IP of Docker Host) and save it as default.conf:
server {
listen 80;
server_name _;
location / {
proxy_pass http://<IP of Docker Host>;
index index.html index.htm;
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root /usr/share/nginx/html;
}
}
Now bring up the container:
docker run -d --name nginx -p 80:80 -v /path/to/nginx/config/default.conf:/etc/nginx/conf.d/default.conf nginx
If you are using Docker Compose file version 3 you don't need any special config for docker-compose.yml file at all, just use the special DNS name host.docker.internal to reach a host service, as on the following nginx.conf example:
events {
worker_connections 1024;
}
http {
upstream host_service {
server host.docker.internal:2345;
}
server {
listen 80;
access_log /var/log/nginx/http_access.log combined;
error_log /var/log/nginx/http_error.log;
location / {
proxy_pass http://host_service;
proxy_set_header Host $http_host;
proxy_set_header X-Real-IP $realip_remote_addr;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_http_version 1.1;
proxy_set_header Connection "";
}
}
}
Solution 1
Use network_mode: host, this will bind your nginx instance to host's network interface.
This could result in conflicts when running multiple nginx containers: every exposed port is binded to host's interface.
Solution 2
I'm running more nginx instances for every service I would like expose to outside world.
To keep the nginx configurations simple and avoid binding every nginx to host use the container structure:
dockerhost - a dummy container with network_mode: host
proxy - nginx container used as a proxy to host service,
link dockerhost to proxy, this will add an /etc/hosts entry in proxy contianer - we can use 'dockerhost' as a hostname in nginx configuration.
docker-compose.yaml
version: '3'
services:
dockerhost:
image: alpine
entrypoint: /bin/sh -c "tail -f /dev/null"
network_mode: host
proxy:
image: nginx:alpine
links:
- dockerhost:dockerhost
ports:
- "18080:80"
volumes:
- /share/Container/nginx/default.conf:/etc/nginx/conf.d/default.conf:ro
default.conf
location / {
proxy_pass http://dockerhost:8080;
This method allows us to have have automated let's encrtypt certificates generated for every service running on my server. If interested I can post a gist about the solution.
server {
listen 80;
server_name localhost;
location / {
proxy_pass http://host.docker.internal:3000;
}
}
Docker expose host address is host.docker.internal in Mac os
There a couple of things you have to keep in mind:
Docker compose (from version 3) by default uses the service name as hostname for inter container networking
Nginx need to know the upstream first
I strongly recommend mounting the default.conf directly into your docker-compose.yml.
Lastly you have to dockerize your backend to make use of docker internal networking.
An example repo where I use nginx and docker-compose in a full-stack project: https://gitlab.com/datails/api.
The following example have some prerequisites:
you have a folder structure like:
- backend/
- frontend/
- default.conf
- docker-compose.yml
Secondly the backend and front-end dit have a Dockerfile that exposes an application on port 3000.
Example default.conf:
upstream backend {
server backend:3000;
}
upstream frontend {
server frontend:3000;
}
server {
listen 80;
location /api {
proxy_pass http://backend;
}
location / {
proxy_pass http://frontend/;
}
}
Example docker-compose.yml:
version: '3.8'
services:
nginx:
image: nginx:1.19.4
depends_on:
- server
- frontend
volumes:
- ./nginx.conf:/etc/nginx/conf.d/default.conf
ports:
- '8080:80'
Then make sure you have your backend dockerized and called (in this case) backend as a service and a front-end (if needed) called frontend as a service in your docker-compose:
version: '3.8'
services:
nginx:
image: nginx:1.19.4
depends_on:
- server
- frontend
volumes:
- ./default.conf:/etc/nginx/conf.d/default.conf
ports:
- '8080:80'
frontend:
build: ./frontend
backend:
build: ./backend
This is a bare minimum example to get started. Hope this will help future developers.
What I want to achive is load balancing using this stack: Docker, Docker Compose, Registrator, Consul, Consul Template, NGINX and, finally, a tiny service that prints out "Hello world" in browser. So, at this moment I have a docker-compose.yml file. It looks like so:
version: '2'
services:
accent:
build:
context: ./accent
image: accent
container_name: accent
restart: always
ports:
- 80
consul:
image: gliderlabs/consul-server:latest
container_name: consul
hostname: ${MYHOST}
restart: always
ports:
- 8300:8300
- 8400:8400
- 8500:8500
- 8600:53/udp
command: -advertise ${MYHOST} -data-dir /tmp/consul -bootstrap -client 0.0.0.0
registrator:
image: gliderlabs/registrator:latest
container_name: registrator
hostname: ${MYHOST}
network_mode: host
restart: always
volumes:
- /var/run/docker.sock:/tmp/docker.sock
command: -ip ${MYHOST} consul://${MYHOST}:8500
nginx:
container_name: nginx
image: nginx:latest
restart: always
volumes:
- /etc/nginx
ports:
- 8181:80
consul-template:
container_name: consul-template
build:
context: ./consul-template
network_mode: host
restart: always
volumes_from:
- nginx
volumes:
- /var/run/docker.sock:/tmp/docker.sock
command: -consul=${MYHOST}:8500 -wait=5s -template="/etc/ctmpl/nginx.ctmpl:/etc/nginx/nginx.conf:docker kill -s HUP nginx"
The first service - accent - is that my web service that I need to load balance. When I run this command:
$ docker-compose up
I see that all services start to run and I see no error messages. It looks as if everything is just perfect. When I run
$ docker ps
I see this in the console:
... NAMES STATUS PORTS
consul-template Up 45 seconds
consul Up 56 seconds 0.0.0.0:8300->8300/tcp, 0.0.0.0:8400->8400/tcp, 8301-8302/tcp, 8301-8302/udp, 0.0.0.0:8500->8500/tcp, 8600/tcp, 8600/udp, 0.0.0.0:8600->53/udp
nginx Up 41 seconds 0.0.0.0:8181->80/tcp
registrator Up 56 seconds
accent Up 56 seconds 0.0.0.0:32792->80/tcp
Please, pay attention to the last row and especially to PORTS column. As you can see, this service publishes 32792 port. To check that my web service is achievable I go to 127.0.0.1:32972 on my host machine (the machine where I run docker compose up) and see this in browser:
Hello World
This is exactly what I wanted to see. However, it is not what I finally want. Please, have a look at the output of docker ps command and you will see, that my nginx service published 8181 port. So, my expectation is that when I go to this address - 127.0.0.1:8181 - I will see exactly the same "Hello world" page. However, it is not. In browser I see Bad Gateway error message and in nginx logs I see this error message
nginx | 2017/01/18 06:16:45 [error] 5#5: *5 connect() failed (111: Connection refused) while connecting to upstream, client: 172.18.0.1, server: , request: "GET /favicon.ico HTTP/1.1", upstream: "http://127.0.0.1:32792/index.php", host: "127.0.0.1:8181"
It is really interesting, because nginx does what I expect it to do - upstreams to "http://127.0.0.1:32792/index.php". But I'm not sure why does it fail. By the way, this is how nginx.conf (created automatically with Consul Template) looks like:
worker_processes 1;
events {
worker_connections 1024;
}
http {
sendfile on;
upstream app_servers {
server 127.0.0.1:32792;
}
server {
listen 80;
root /code;
index index.php index.html;
location / {
try_files $uri/ $uri/ /index.php;
}
location ~ \.php$ {
proxy_pass http://app_servers;
proxy_redirect off;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Host $server_name;
}
location ~ /\.ht {
deny all;
}
}
}
I wouldn't change anything, since this nginx.conf looks good to me. Trying to understand why it does not work, I shelled to nginx container and made a couple of commands:
$ curl accent
Hello World
$ curl 127.0.0.1:32972
curl: (7) Failed to connect to 127.0.0.1 port 32972: Connection refused
$ curl accent:32972
curl: (7) Failed to connect to accent port 32972: Connection refused
Again, it is interesting, because nginx container sees my web service under port 80 and not under its published 32972 port. Anyway, at this stage I do not know why it does not work and how to fix it. I just have a guess, that it is somehow connected to the way, how network is configured in docker-compose.yml. I tried various combinations of network_mode: host on accent and nginx service, but to no avail - either accent stops working or nginx or both. So, I need some help.
When you do port binding it publish some port from container (80 in accent e.g.) and some port on your host (random 32792 on host e.g.).Containers in same network as your accent container can access your container port 80 by accent (same as accent:80) due to docker-compose services name resolving. You can access accent:80 from your host with accent:32792. When you are requesting 127.0.0.1:32792 from your nginx container you can access only nginx container 32792 port, not accent. accent:32792 is not correct url from anyway (80 port open on accent, 32792 on host). But 127.0.0.1:32792 should work when you add nginx container to host network. But I noticed that you use incorrect port in curl call. Your accent:80 published to host 32792 but you request 32972.