Nginx reverse proxy can't reach docker host. Hosting on amazon (EC2)
I want to load different apps depends on location.
nginx.conf
server {
listen 80 ;
server_name localhost;
location /web {
proxy_pass http://web:4000/;
}}
Location works and it means that nginx image builded correct either.
docker-compose file
services:
web:
image: web
container_name: web
ports:
- 4000:4000
hostname: web
networks:
- default
nginx:
image: nginx
container_name: nginx
ports:
- 80:80
depends_on:
- web
networks:
- default
networks:
default:
external:
name: my-network
I expect
- when I type in url /web it should show app from docker container
I've tried
Run single container - works fine (web or nginx)
Added 127.0.0.1 web in /etc/hosts (I can do 'curl web' but it shows localhost response)
Added index index.html in location section
Added resolver in the location section
Use links instead of network
When "docker-compose up" I can inspect docker container (web) and see IP - 192.168.10.2 . Then curl 192.168.10.2 shows me index.html. But I can't make curl http://web:4000 seems that hostname in unreachable, but I think that using IP in proxy_pass is a bad decision.
I wasn't able to handle those issues, so I've chose another approach.
Create network ipam
docker network create --gateway 172.20.0.1 --subnet 172.20.0.0/24 ipam
Assigned for each service ipv4address in docker-compose file
networks:
default:
ipv4_address: 172.20.0.5 for web
where
networks:
default:
external:
name: ipam
Add chmod for directory /var/www/html in my web docker image
chmod -R 755 /var/www/html
(seems this additional step required if you build LINUX container under windows docker)
Related
i'm new to docker networking and nginx stuff, but try to "dockerize" everything on a local devserver. for tests a docker image with nginx which should redirect another container (gogs) from port 3000 to a specific url with port 80. And i want to have the reverse proxy configs and the docker images "separated", for each "app" an own docker-compose file.
so i should reach with http://app.test.local the gog installation.
BUT: i reach with http://app.test.local only a bad gateway of nginx and with http://app.test.local:3000 i reach the gog installation...
i tried many tutorials, but somehwere there have to be an error, thats slips in every time
so what i did:
$ docker network create testserver-network
created
docker-compose for nginx:
version: '3'
services:
proxy:
container_name: proxy
hostname: proxy
image: nginx
ports:
- 80:80
- 443:443
volumes:
- /docker/proxy/config:/etc/nginx
- /docker/proxy/certs:/etc/ssl/private
networks:
- testserver-network
networks:
testserver-network:
and one for gogs:
version: '3'
services:
gogs:
container_name: gogs
hostname: gogs
image: gogs/gogs
ports:
- 3000:3000
- "10022:22"
volumes:
- /docker/gogs/data:/var/gogs/data
networks:
- testserver-network
networks:
testserver-network:
(mapped directories work)
configured default.conf of nginx:
# upstream gogs {
# server 0.0.0.0:10880;
# }
server {
listen 80;
server_name app.test.local;
location / {
proxy_pass http://localhost:3000;
}
}
and added to hosts file on client
app.test.local <server ip>
docker exec proxy nginx -t and docker exec proxy nginx -s reload say everythings fine...
Answer
You should connect both containers to the same docker network and then proxy to http://gogs:3000 instead. You also shouldn't need to expose port 3000 on your localhost unless you want http://app.test.local:3000 to work. I think ideally you should remove that, so http://app.test.local should proxy to your gogs server, and http://app.test.local:3000 should error out.
Explanation
gogs is exposed on port 3000 inside its container, which is then further exposed on port 3000 on your host machine. The nginx container does not have access to port 3000 on your host, so when it tries to proxy to http://localhost:3000 it is proxying to port 3000 inside the nginx container (which is hosting nothing).
After you have joined the containers to the same network, you should be able to reference the gogs container from the nginx container by its hostname (which you've set to gogs). Now nginx will proxy through the docker network. So you should be able to perform the proxy without needing to expose 3000 on your local machine.
I've this docker-compose file:
version: "3.8"
services:
web:
image: apachephp:v1
ports:
- "80-85:80"
volumes:
- volume:/var/www/html
network_mode: bridge
ddbb:
image: mariadb:v1
ports:
- "3306:3306"
volumes:
- volume2:/var/lib/mysql
network_mode: bridge
environment:
- MYSQL_ROOT_PASSWORD=*********
- MYSQL_DATABASE=*********
- MYSQL_USER=*********
- MYSQL_PASSWORD=*********
volumes:
volume:
name: volume-data
volume2:
name: volume2-data
When run this:
docker-compose up -d --scale web=2
Its works as well but receive this warning:
WARNING: The "web" service specifies a port on the host. If multiple containers for this service are created on a single host, the port will clash.
Can somebody help to avoid these warning?, thank you advance.
Best regards.
I suppose, you try to access the web service without knowing the port of the specific container and to distribute the requests to a container here. If i rigth, to do that, you need a load balancing mechanisms to the system configuration.In the following example, i'll use NGINX as the load balancer.
version: "3.8"
services:
web:
image: apachephp:v1
expose: # change 'ports' to 'expose'
- "7483" # <- this is web running port (Change to your web port)
....
ddbb:
....
## New Start ##
nginx:
image: nginx:latest
volumes:
- ./nginx.conf:/etc/nginx/nginx.conf:ro
depends_on:
- web # your web service name
ports:
- "80:80"
## New End ##
volumes:
...
So you don’t need to map the port 80-85:80 from the web services to a host machine port, if you want to scale the service. So i remove the port mapping configuration from your Docker Compose file and only expose the port as above:
In the nginx service and i add port mappings to the host container for that server. In example, i configured NGINX to listen on the port 4000, which is why we have to add port mappings for this port.
nginx.conf file contents:
user nginx;
events {
worker_connections 1000;
}
http {
server {
listen 4000;
location / {
proxy_pass http://pspdfkit:5000;
}
}
}
You will find here more details, to Use Docker Compose to Run Multiple Instances of a Service in Development.
I have tried reading through the other stackoverflow questions here but I am either missing something or none of them are working for me.
Context
I have two docker containers setup on a DigitalOcean server running Ubuntu.
root_frontend_1 running on ports 0.0.0.0:3000->3000/tcp
root_nginxcustom_1 running on ports 0.0.0.0:80->80/tcp
If I connect to http://127.0.0.1, I get the default Nginx index.html homepage. If I http://127.0.0.1:3000 I am getting my react app.
What I am trying to accomplish is to get my react app when I visit http://127.0.0.1. Following the documentation and suggestions here on StackOverflow, I have the following:
docker-compose.yml in root of my DigitalOcean server.
version: "3"
services:
nginxcustom:
image: nginx
hostname: nginxcustom
ports:
- "80:80"
volumes:
- ./nginx.conf:/root/nginxcustom/conf/custom.conf
tty: true
backend:
build: https://github.com/Twitter-Clone/twitter-clone-api.git
ports:
- "8000:8000"
tty: true
frontend:
build: https://github.com/dougmellon/react-api.git
ports:
- "3000:3000"
stdin_open: true
tty: true
nginxcustom/conf/custom.conf :
server {
listen 80;
server_name http://127.0.0.1;
location / {
proxy_pass http://root_frontend_1:3000; # this one here
proxy_redirect off;
}
}
When I run docker-compose up, it builds but when I visit the ip of my server, it's still showing the default nginx html file.
Question
What am I doing wrong here and how can I get it so the main URL points to my react container?
Thank you for your time, and if there is anything I can add for clarity, please don't hesitate to ask.
TL;DR;
The nginx service should proxy_pass to the service name (customnginx), not the container name (root_frontend_1) and the nginx config should be mounted to the correct location inside the container.
Tip: the container name can be set in the docker-compose.yml for services setting the container_name however beware you can not --scale services with a fixed container_name.
Tip: the container name (root_frontend_1) is generated using the compose project name which defaults to using the current directory name if not set.
Tip: the nginx images are packaged with a default /etc/nginx/nginx.conf that will include the default server config from /etc/nginx/conf.d/default.conf. You can docker cp the default configuration files out of a container if you'd like to inspect them or use them as a base for your own configuration:
docker create --name nginx nginx
docker cp nginx:/etc/nginx/conf.d/default.conf default.conf
docker cp nginx:/etc/nginx/nginx.conf nginx.conf
docker container rm nginx
With nginx proxying connections for the frontend service we don't need to bind the hosts port to the container, the services ports definition can be replaced with an expose definition to prevent direct connections to http://159.89.135.61:3000 (depending on the backend you might want prevent direct connections as well):
version: "3"
services:
...
frontend:
build: https://github.com/dougmellon/react-api.git
expose:
- "3000"
stdin_open: true
tty: true
Taking it a step further we can configure an upstream for the
frontend service then configure the proxy_pass for the upstream:
upstream frontend {
server frontend:3000 max_fails=3;
}
server {
listen 80;
server_name http://159.89.135.61;
location / {
proxy_pass http://frontend/;
}
}
... then bind-mount the custom default.conf on top of the default.conf inside the container:
version: "3"
services:
nginxcustom:
image: nginx
hostname: nginxcustom
ports:
- "80:80"
volumes:
- ./default.conf:/etc/nginx/conf.d/default.conf
tty: true
... and finally --scale our frontend service (bounce the services removing the containers to make sure changes to the config take effect):
docker-compose stop nginxcustom \
&& docker-compose rm -f \
&& docker-compose up -d --scale frontend=3
docker will resolve the service name to the IP's of the 3 frontend containers which nginx will proxy the connections for in a (by default) round robin manner.
Tip: you can not --scale a service that has ports mappings, only a single container can bind to the port.
Tip: if you've updated the config and can connect to your load balanced service then you're all set to create a DNS record to resolve a hostname to your public IP address then update your default.conf's server_name.
Tip: for security I maintain specs for building a nginx docker image with Modsecurity and Modsecurity-nginx pre-baked with the OWASP Core Rule Set.
In Docker when multiple services needs to communicate with each other, you can use the service name in the url (set in the docker-composer.yml instead of the ip (which is attributed from the available pool of the network, default by default), it will automatically be resolve to the right container ip due to network management by docker.
For you it would be http://frontend:3000
I'm trying to follow this guide to setting up a reverse proxy for a docker container (serving a static file), using another container with an instance of nginx as a reverse proxy.
I expect to see my page served on /, but I am blocked in the build with the error message:
container_nginx_1 | 2020/05/10 16:54:12 [emerg] 1#1: host not found in upstream "container1:8001" in /etc/nginx/conf.d/sites-enabled/virtual.conf:2
container_nginx_1 | nginx: [emerg] host not found in upstream "container1:8001" in /etc/nginx/conf.d/sites-enabled/virtual.conf:2
nginx_docker_test_container_nginx_1 exited with code 1
I have tried many variations on the following virtual.conf file, and this is the current, based on the example given and various other pages:
upstream cont {
server container1:8001;
}
server {
listen 80;
location / {
proxy_pass http://cont/;
}
}
If you are willing to look at a 3rd party site, I've made a minimal repo here, otherwise the most relevant files are below.
My docker-compose file looks like this:
version: '3'
services:
container1:
hostname: container1
restart: always
image: danjellz/http-server
ports:
- "8001:8001"
volumes:
- ./proj1:/public
command: "http-server . -p 8001"
depends_on:
- container_nginx
networks:
- app-network
container_nginx:
build:
context: .
dockerfile: docker/Dockerfile_nginx
ports:
- 8080:8080
networks:
- app-network
networks:
app-network:
driver: bridge
and the Dockerfile
# docker/Dockerfile_nginx
FROM nginx:latest
# add nginx config files to sites-available & sites-enabled
RUN mkdir /etc/nginx/conf.d/sites-available
RUN mkdir /etc/nginx/conf.d/sites-enabled
ADD projnginx/conf.d/sites-available/virtual.conf /etc/nginx/conf.d/sites-available/virtual.conf
RUN cp /etc/nginx/conf.d/sites-available/virtual.conf /etc/nginx/conf.d/sites-enabled/virtual.conf
# Replace the standard nginx conf
RUN sed -i 's|include /etc/nginx/conf.d/\*.conf;|include /etc/nginx/conf.d/sites-enabled/*.conf;|' /etc/nginx/nginx.conf
WORKDIR /
I'm running this using docker-compose up.
Similar: react - docker host not found in upstream
The problem is if the hostname can not be resolved in upstream blocks, nginx will not start. Here you have defined service container1 to be dependent on container_nginx . But nginx container is never up due to the fact the container1 hostname is not resolved (because container1 is not yet started) Don't you think it should be reverse? Nginx container should be dependent on the app container.
Additionally in your nginx port binding you have mapped 8080:8080 while in nginx conf you have 80 listening.
Hello I'm new to the world of Docker, so I tried an installation with NGINX reverse proxy (jwilder image) and a Docker app.
I have installed both without SSL to make it easy. Since the Docker app seems to be installed in the root path I want to separate the NGINX web server and the docker app.
upstream example.com {
server 172.29.12.2:4040;
}
server {
server_name example.com;
listen 80 ;
access_log /var/log/nginx/access.log vhost;
location / {
proxy_pass http://example.com;
root /usr/share/nginx/html;
index index.html index.htm;
}
location /app {
proxy_pass http://example.com:4040;
}
}
So I want with http://example.com be redirected to the index.html
and with http://example.com/app be redirected to the docker app.
Furthermore, when I build the installation, I use in docker-compose expose: "4040" so when I reload NGINX configuration file with nginx -s reload, it warns me that I have not the port 4040 open.
With the configuration file I posted above any path lead me to the docker app.
I can't find a simple solution to my question.
As I far I understood your logic is right, docker is designed to run a single service to a single container; to reach your goal you still have a couple of thing to look after, if the EXPOSE 4040 was declared in you Docker file, that is not enough to let service reachable. in the docker-compose file you have to declare also the ports, I.E. for nginx you let host system to listen on all interface by adding
...
ports:
- 80:80
...
and this is the first thing, also you have to think on which way you want your proxy reach the "app", from the container network on the same node? If yes you can add in the composer file:
...
depends_on:
- app
...
where app is the declared name of your service in the docker-compose file like this nginx are able to reach your app with name app, so redirect will point to app:
location /app {
proxy_pass http://app:4040;
}
In case you want to reach the "app" via host network, may because one day will run in another host, you can add entry in the hosts file of the container run nginx with:
...
extra_hosts:
- "app:10.10.10.10"
- "appb:10.10.10.11"
...
and so on
Reference: https://docs.docker.com/compose/compose-file/
edit 01/01/2019!!!!! happy new year!!
an example using an "huge" docker compose file:
version: '3'
services:
app:
build: "./app" # in case you docker file is in a app dir
image: "some image name"
restart: always
command: "command to start your app"
nginx:
build: "./nginx" # in case you docker file is in a nginx dir
image: "some image name"
restart: always
ports:
- "80:80"
- "443:443"
depends_on:
- app
In the above example nginx can reach yuor app just with the "app" name so redirect will point to http://app:4040
systemctl (start directly with docker - no compose)
[Unit]
Description=app dockerized service
Requires=docker.service
After=docker.service
[Service]
ExecStartPre=/usr/bin/sleep 1
ExecStartPre=/usr/bin/docker pull mariadb:10.4
ExecStart=/usr/bin/docker run --restart=always --name=app -p 4040:4040 python:3.6-alpine # or your own builded image
ExecStop=/usr/bin/docker stop app
ExecStopPost=/usr/bin/docker rm -f app
ExecReload=/usr/bin/docker restart app
[Install]
WantedBy=multi-user.target
like the above example you can reach the app at port 4040 on the system host (which is in listen for connection on port 4040 by all interfaces) to give a specific interface: -p 10.10.10.10:4040:4040 like this will listen to port 4040 on address 10.10.10.10 (host machine)
docker-compose with extra_host:
version: '3'
services:
app:
build: "./app" # in case you docker file is in a app dir
image: "some image name"
restart: always
command: "command to start your app"
nginx:
build: "./nginx" # in case you docker file is in a nginx dir
image: "some image name"
restart: always
ports:
- "80:80"
- "443:443"
extra_hosts:
- "app:10.10.10.10"
like the above example nginx defined service can reach the name app at 10.10.10.10
least but not last extends service on compose file:
docker-compose.yml:
version: '2.1'
services:
app:
extends:
file: /path/to/app-service.yml
service: app
nginx:
extends: /path/to/nginx-service.yml
service: nginx
app-service.yml:
version: "2.1"
service:
app:
build: "./app" # in case you docker file is in a app dir
image: "some image name"
restart: always
command: "command to start your app"
nginx-service.yml
version: "2.1"
service:
nginx:
build: "./nginx" # in case you docker file is in a nginx dir
image: "some image name"
restart: always
ports:
- "80:80"
- "443:443"
extra_hosts:
- "app:10.10.10.10"
really hope the above posted are enough examples.