Nginx Proxy Upstream Server Docker Compose - 502 Bad Gateway Connection Refused - docker

I am trying to containerize all things related to my web app using Docker Compose, including Nginx & SSL Certificates. To do this I am using the Nginx Proxy image from JWilder and the LetsEncrypt Companion, but am having trouble getting the nginx proxy to work, result ends up being:
Nginx 502 Bad Gateway
[error] 31160#0: *35 connect() failed (111: Connection refused) while connecting to upstream, client: xx.xx.xx.xx, server: domain.com, request: "GET /dev/ HTTP/1.1", upstream: "webapp://127.0.0.1:8080", host: "domain.com"
This only happened when trying to set up the Nginx proxy and SSL certificates so I know it's a configuration issue for either or both of these containers. If anyone can spot where I am going wrong, I would be extremely grateful!
Here are the containers in question:
version: '3.1'
networks:
mywebapp:
services:
nginx-proxy:
container_name: nginx-proxy
build: ./env/nginx-proxy
networks:
- mywebapp
ports:
- 80:80
- 443:443
env_file:
- ./env/nginx-proxy/.env
depends_on:
- webapp
tty: true
volumes:
- ./src:/home/www/mywebapp/src
- ./storage:/home/www/storage/mywebapp
- ./data/nginx-proxy/logs:/var/log/nginx
- ./env/nginx-proxy/webserver/nginx.conf:/etc/nginx/nginx.conf
- ./env/nginx-proxy/webserver/conf.d:/etc/nginx/conf.d
- ./env/nginx-proxy/webserver/vhost.d:/etc/nginx/vhost.d
- ./env/nginx-proxy/webserver/defaults:/etc/nginx/defaults
- ./env/nginx-proxy/webserver/global:/etc/nginx/global
- ./env/nginx-proxy/ssl/certs:/etc/nginx/certs
- ./env/nginx-proxy/share:/usr/share/nginx/html
- /var/run/docker.sock:/tmp/docker.sock:ro
labels:
com.github.jrcs.letsencrypt_nginx_proxy_companion.nginx_proxy: "true"
letsencrypt:
restart: always
container_name: letsencrypt
image: jrcs/letsencrypt-nginx-proxy-companion
env_file:
- ./env/letsencrypt/.env
volumes:
- ./data/letsencrypt/logs:/var/log
- ./env/nginx-proxy/webserver/nginx.conf:/etc/nginx/nginx.conf
- ./env/nginx-proxy/webserver/conf.d:/etc/nginx/conf.d
- ./env/nginx-proxy/webserver/vhost.d:/etc/nginx/vhost.d
- ./env/nginx-proxy/webserver/defaults:/etc/nginx/defaults
- ./env/nginx-proxy/webserver/global:/etc/nginx/global
- ./env/nginx-proxy/ssl/certs:/etc/nginx/certs
- ./env/nginx-proxy/share:/usr/share/nginx/html
- /var/run/docker.sock:/var/run/docker.sock:ro
depends_on:
- nginx-proxy
webapp:
container_name: webapp
build: ./env/webapp
hostname: webapp
networks:
- mywebapp
ports:
- 9000:9000
- 8080:8080
volumes:
- ./env/composer:/home/www/.composer
- ./env/global/bashrc:/home/www/.bashrc
- ./data/bash/.bash_history:/home/www/.bash_history
- ~/.ssh:/home/www/.ssh:ro
- ~/.gitconfig:/home/www/.gitconfig:ro
- ./storage:/home/www/storage/mywebapp
- ./src:/home/www/mywebapp/src
Key points being:
Webapp is the source of my web application which is running PHP, MySQL and Nginx webserver. The webapp webserver exposes and listens on port 8080 to serve the PHP files.
Nginx proxy exposes standard ports 443 and 80 and proxy passes to webapp on port 8080
LetsEncrypt Companion generates the certs and renews.
Nginx Proxy server configuration:
upstream webapp {
server 127.0.0.1:8080;
}
server {
listen 80;
listen [::]:80;
server_name webapp.localhost;
location / {
proxy_pass http://webapp;
}
}
server {
# SSL configuration
listen 443 ssl http2;
listen [::]:443 ssl http2;
ssl_certificate certs/default.crt;
ssl_certificate_key certs/default.key;
include /etc/nginx/global/ssl-params.conf;
server_name webapp.localhost;
location / {
proxy_pass http://webapp;
}
}
Webapp webserver configuration:
server {
listen 8080;
listen [::]:8080;
server_name webapp.localhost;
root /home/www/webapp/src;
index index.php;
include /etc/nginx/defaults/php.conf;
location / {
try_files $uri $uri/ /index.php$is_args$args;
}
}
When visiting http://webapp.localhost:8080 I can see the webapp webserver serves the page no trouble, so I suspect it's something wrong with my Nginx Proxy server configuration.
Thanks for reading.

Since nginx and webapp are on two separate containers, nginx can't reach webapp on localhost(127.0.0.1) as you've configured for upstream:
upstream webapp {
server 127.0.0.1:8080;
}
Change it to webapp:8080.

Related

Deploying a Docker container with Nginx and FastAPI on Google Cloud Platform from SSH-term

I have a some issue when trying to deploy a simple FastAPI application with Nginx on Google Cloud Platform. In my case I should use SSH-terminal to run Docker container with Nginx and FastAPI. My nginx.conf configuration looks like:
access_log /var/log/nginx/app.log;
error_log /var/log/nginx/app.log;
server {
server_name example.com;
listen 80;
return 301 https://$host$request_uri;
}
server {
listen 443 ssl;
server_name example.com;
ssl_certificate /root/ssl/cert.pem;
ssl_certificate_key /root/ssl/key.pem;
location / {
proxy_pass "http://example.com:8004/";
}
}
And my docker-compose.yml looks like:
version: '3.8'
services:
nginx-proxy:
image: nginx
container_name: nginx-proxy
ports:
- "80:80"
- "443:443"
volumes:
- /var/run/docker.sock:/tmp/docker.sock:ro
- ./nginx:/etc/nginx/conf.d
- ./ssl/cert1.pem:/root/ssl/cert.pem
- ./ssl/privkey1.pem:/root/ssl/key.pem
- ./ssl/dhparam.pem:/etc/nginx/dhparam/dhparam.pem
web:
environment: [.env]
build: ./project
ports:
- 8004:8000
command: gunicorn main:app -k uvicorn.workers.UvicornWorker -w 2 -b 0.0.0.0:8000
volumes:
- ./project:/usr/src/app
networks:
default:
external:
name: nginx-proxy
Also, I have a Google Cloud VM instance with Firewall HTTP, HTTPS traffic On option, and additionally configured Firewall with rules allowed TCP connections over 443 and 80 ports (Domain name is provided by Google Cloud also, and redirects to VM's external IP address when I put it in my browser address field).
I run my docker-image from SSH-terminal with docker-compose up --build, then I get 502 Bad Gateway Nginx error in my browser (after going to example.com). I would like to know whether it is possible to run the docker image this way from inside SSH-terminal, as well as which steps did I miss to do it the right way?

502 Bad Gateway when using reverse proxy with Docker and Nginx

I have searched StackOverflow for my problem but I always seem to be hitting the 502 Bad Gateway with my Nginx Docker configuration. I am trying to access pgadmin4 using my domain mydomain.com/pgadmin instead of mydomain.com:8060 where 8060 is the port exposed by it's docker container. My docker-compose.yml file looks like this:
version: '3.5'
services:
reverse-proxy:
image: nginx:1.19.6
restart: always
ports:
- "80:80"
- "443:443"
postgres:
image: postgres:12
ports:
- "5432:5432"
pgadmin:
image: dpage/pgadmin4
depends_on:
- postgres
ports:
- "8060:80"
networks:
default:
external:
name: defaultnetwork
The default.conf file of my nginx container looks like this:
upstream pgadmin {
server 127.0.0.1:8060;
}
server {
listen 80;
listen [::]:80;
server_name mydomain.com;
root /usr/share/nginx/html;
index index.html index.htm;
location /pgadmin {
proxy_pass http://pgadmin;
}
}
With this configuration, I keep getting the 502 Bad Gateway error. Could someone kindly point to me where I am going wrong. I would really appreciate it.
Thanks.
[EDIT]
This is from the docker logs:
2021/02/03 08:07:42 [error] 23#23: *2 connect() failed (111: Connection refused) while connecting to upstream, client: ***.***.***.***, server: mydomain.com, request: "GET /pgadmin HTTP/1.1", upstream: "http://127.0.0.1:8082/pgadmin", host: "mydomain.com"
The 502 problem comes from the loopback IP here:
upstream pgadmin {
server 127.0.0.1:8060;
}
127.0.0.1 or localhost for the NGINX container is the NGINX container itself. You should use the name of the service instead:
upstream pgadmin {
server pgadmin:8060;
}
Name of the service comes from the docker-compose.yml:
services:
pgadmin: # <- this
image: dpage/pgadmin4
If you hit 404 after these changes, this is because you have to change base path of the application. Try using this config:
location /pgadmin/ {
proxy_set_header X-Script-Name /pgadmin;
proxy_set_header Host $host;
proxy_pass http://pgadmin;
proxy_redirect off;
}
Since your containers are working in the same network, you should access the Pgadmin container via 80th port from your Nginx container.
You should replace this line server 127.0.0.1:8060 with server pgadmin:80 in your Nginx config.

docker nginx proxy to linked container not working

I have tried this:
NGINX reverse proxy not working to other docker container
and this:
Docker nginx-proxy : proxy between containers
and followed nginx config from here:
nginx proxy_pass to a linked docker container
I am simply trying to tell nginx to proxy to a linked api service on port 4000. I do not want to expose 4000 to host machine because there will be multiple services running on this port.
This is my docker-compose.yml:
version: '3'
services:
api:
build: ./api
image: myapi:latest
container_nameE: api
api_nginx:
image: nginx:latest
container_name: api_nginx
depends_on:
- api
links:
- api
ports:
- "80:80"
environment:
- NGINX_SERVER_NAME:localhost
volumes:
- ./nginx:/etc/nginx/conf.d
...
...
and my nginx server is super minimal:
upstream backend {
server api;
}
server {
listen 80;
listen [::]:80;
server_name ${NGINX_SERVEE_NAME};
location / {
resolver 127.0.0.1;
proxy_pass http://backend/$1;
}
}
This is the error is throwing:
...[error] 20#20: *1 no resolver defined to resolve api, client: 172.23.0.1, server: ${nginx_server_name}....
and the page shows a 502 Bad Gateway
What is going on? I've followed other people's nginx configs and it's not working, I have no idea.

Docker compose & nginx network hostnames

I have the following configuration:
nginx started by a docker compose file acting as reverse proxy // ssl endpoint
an application service started by a different docker compose (for modularity reasons) file serving a application
reverse_proxy and app_service are connected via the app_network
Since they are connected via the app_network, I am able to address the app_service in the nginx configuration like http://app_service:8080, which is nice because I don't need to expose ports on the app service itself.
Unfortunately, nginx won't start until I brought up the app service container because it checks the existance of the hostname app_service upon startup.
How can I prevent nginx from checking the hostname on startup, maybe causing a Bad Gateway error when trying to connect while app_service is not running yet?
Configuration files for reference:
# reverse proxy docker-compose.yml
version: '3'
services:
reverse_proxy:
restart: always
container_name: reverse_proxy
image: nginx
ports:
- 80:80
- 443:443
volumes:
- /srv/docker/nginx/config:/etc/nginx
- /srv/ssl:/srv/ssl
networks:
default:
external:
name: app_network
# application service docker-compose.yml
version: '3'
services:
app_service:
restart: always
container_name: app_service
image: <my_app_image>
networks:
default:
external:
name: app_network
# nginx config
server {
listen 443 ssl http2;
listen [::]:443 ssl http2;
server_name app.example.com;
location / {
proxy_pass http://app_service:8080;
include proxy.conf;
}
ssl_certificate /srv/ssl/<mycert>.crt;
ssl_certificate_key /srv/ssl/<mykey>.key;
}
Here is a way that worked for me:
# nginx config
server {
listen 443 ssl http2;
listen [::]:443 ssl http2;
server_name app.example.com;
location / {
set $upstream app_service:8080;
proxy_pass $upstream;
include proxy.conf;
}
ssl_certificate /srv/ssl/.crt;
ssl_certificate_key /srv/ssl/.key;
}
This results in a 502 Bad Gateway message if the host is unavailable and does not check availability at startup.

Nginx reverse proxy (in Docker) to a web app (also in Docker)

I have set up a web application in docker which is currently running internal to the host at 172.19.0.3:8888. I want this web application accessible over the internet on port 443 (https), with requests to port 80 (HTTP) redirected to 443.
I plan to use an Nginx reverse proxy in a docker container to achieve this, but I do not know how to properly configure it to point at the docker container 172.19.0.3:8888. Accessing http://172.19.0.3:8888 from the host works.
Here is the guide I tried to follow, but it just didn't show how to point at a docker container specifically.
https://medium.com/#pentacent/nginx-and-lets-encrypt-with-docker-in-less-than-5-minutes-b4b8a60d3a71
Note
If I set the port 443 proxy_pass to http://example.org, it works. So Cert configurations are working correctly.
Web application
Running on 172.19.0.3:8888 internal to the host
docker-compose for Nginx and Certbot
My certs are coming back clean.
version: '3'
services:
nginx:
image: nginx:1.15-alpine
ports:
- "80:80"
- "443:443"
volumes:
- ./Volumes/nginx:/etc/nginx/conf.d
- ./Volumes/certbot/conf:/etc/letsencrypt
- ./Volumes/certbot/www:/var/www/certbot
certbot:
image: certbot/certbot
volumes:
- ./Volumes/certbot/conf:/etc/letsencrypt
- ./Volumes/certbot/www:/var/www/certbot
Nginx app.conf
server {
listen 80;
server_name forums.example.com;
location /.well-known/acme-challenge/ {
root /var/www/certbot;
}
location / {
return 301 https://$host$request_uri;
}
}
server {
listen 443 ssl;
server_name forums.example.com;
ssl_certificate /etc/letsencrypt/live/forums.example.com/fullchain.pem;
ssl_certificate_key /etc/letsencrypt/live/forums.example.com/privkey.pem;
include /etc/letsencrypt/options-ssl-nginx.conf;
ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;
location / {
proxy_pass http://172.19.0.3:8888/;
}
}
Web Application
flarum:
image: mondedie/docker-flarum:0.1.0-beta.8.1-stable
container_name: flarum
env_file:
- ./flarum.env
volumes:
- ./Volumes/assets:/flarum/app/public/assets
- ./Volumes/extensions:/flarum/app/extensions
- ./Volumes/nginx:/etc/nginx/conf.d
depends_on:
- mariadb
mariadb:
image: mariadb:10.2
container_name: mariadb
environment:
- MYSQL_ROOT_PASSWORD=password
- MYSQL_DATABASE=flarum
- MYSQL_USER=flarum
- MYSQL_PASSWORD=password
volumes:
- ./Volumes/mysql/db:/var/lib/mysql
Docker Compose creates a seprate network for docker-compose.yaml file.
So you can add your web application as service (eg: webapp) in current compose file. And in nginx.conf directly point to your service. Rather than using IP you can use the service name as DNS which will resolve by Docker for the same network.
location / {
proxy_pass http://webapp:8888/;
}

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