I'm a newbie to Nginx. I cannot access my Node.js application that I deploy on AWS EC2 using Nginx reverse proxy. If I do curl http://localhost:3000 I can see the application is running successfully on the server(I'm using pm2 for running node server). But when I try to access it in my browser or postman using public DNS I get the error This site can't be reached and the request gets timeout. Here's my Nginx configuration (I have followed a number of tutorials for this)
The configuration file is named nginx.conf and is in /etc/nginx/sites-enabled directory. If I do sudo nginx -t it says syntax is ok and the test is successful. Also I can see the Nginx is running using command sudo systemctl status nginx What could be the possible reason for this behaviour?
I figured it out the problem wasn't with the Nginx configuration actually I needed to allow public access for port 80 on my ec2 instance which is blocked by default. I allowed port 80 and everything is working fine. This blog helped me. Visit it for me details on how to enable port 80 for your ec2 instance.
I tried to set an nginx proxy with let's encrypt, all dockerized, by following this tutorial :
http://www.automationlogic.com/using-lets-encrypt-and-docker-for-automatic-ssl/
The problem is that my application exposes port 1337 instead of 80, and I can't change this for now.
Do someone know how I could tell nginx to listen on the app container's at 1337?
After looking at that tutorial and the available source code, the nginx configuration files are using a placeholder _APPLICATION_PORT_ which gets replaced with the nginx docker container's environment variable $APP_PORT_80_TCP_PORT in it's start.sh script. It appears that specific environment variable would need to be added to the docker-compose.yml file:
nginx:
environment:
- APP_PORT_80_TCP_PORT=1337
You would also need to make sure that the docker-compose.yml has the correct port for your application (if docker-compose is launching your application container) so docker exposes the correct port.
Hope that helps
Here I setup two ubuntu machine which had run as docker registry. I just use the Docker Registry latest Image. Then I setup a ubuntu machine running Nginx which will proxy the request to either of the registries.
I changed the Nginx configuration file so I can see "/Docker registry server/" when I "curl" the Nginx server.
But things has been strange when I want to push my Image.
"dial tcp: docker-registry: no such host
Because I setup 3 docker containers on 3 different hosts. Layers of one images maybe post to different registries.
I have an nginx docker container and a webapp container successfully running and talking to eachother.
The nginx container listens on port 80, and uses proxy_pass to direct traffic to the IP of the webapp container.
upstream app_humansio {
server humansio:8080 max_fails=3 fail_timeout=30s;
}
"humansio" is set in the /etc/hosts file by docker because I've started nginx with --link humansio:humansio. The webapp container (humansio) is always exposing 8080.
The problem is, when I reload the webapp container, the link to the nginx container breaks and I need to restart that as well. Is there any way I can do this differently so I don't need to restart the nginx container when the webapp container reloads?
--
I've tried to do something like connecting them manually by using a common port (8001 on both), but since they actually reserve that port, the 2nd container cannot use it as well.
Thanks!
I prefer to run the proxy (nginx of haproxy) directly on the host for this reason.
But an option is to "Link via an Ambassador Container" https://docs.docker.com/articles/ambassador_pattern_linking/
https://www.digitalocean.com/community/tutorials/how-to-use-the-ambassador-pattern-to-dynamically-configure-services-on-coreos
If you don't want to restart your proxy container whenever you have to restart one of the proxied ones (e.g. fig), you could take a look at the autoupdated proxy configuration approach: http://jasonwilder.com/blog/2014/03/25/automated-nginx-reverse-proxy-for-docker/
if u use some modern version of docker the links in nginx container to your web service probably get updated (u can check it with docker exec -ti nginx bash - then cat /etc/hosts) - problem is nginx doesnt' use /etc/hosts every time - it caches the ip and when it changes - he gets lost. 'docker kill -s HUP nginx' which makes nginx reload its config without restart helps too.
I have the same problem. I used to start my services with systemd unit files - and when u make one service (nginx) dependant on other (webapp) and then restart the webapp - systemd is smart enough to restart the nginx as well. Now I'm trying my luck with docker-compose and restarting webapp container confuses nginx.
I have a wildcard DNS set up so that all web requests to a custom domain (*.foo) map to the IP address of the Docker host. If I have multiple containers running Apache (or Nginx) instances, each container maps the Apache port (80) to some external inbound port.
What I would like to do is make a request to container-1.foo, which is already mapped to the correct IP address (of the Docker host) via my custom DNS server, but proxy the default port 80 request to the correct Docker external port such that the correct Apache instance from the specified container is able to respond based on the custom domain. Likewise, container-2.foo would proxy to a second container's apache, and so on.
Is there a pre-built solution for this, is my best bet to run an Nginx proxy on the Docker host, or should I write up a node.js proxy with the potential to manage Docker containers (start/stop/reuild via the web), or...? What options do I have that would make using the Docker containers more like a natural event and not something with extraneous ports and container juggling?
This answer might be a bit late, but what you need is an automatic reverse proxy. I have used two solutions for that:
jwilder/nginx-proxy
Traefik
With time, my preference is to use Traefik. Mostly because it is well documented and maintained, and comes with more features (load balancing with different strategies and priorities, healthchecks, circuit breakers, automatic SSL certificates with ACME/Let's Encrypt, ...).
Using jwilder/nginx-proxy
When running a Docker container Jason Wilder's nginx-proxy Docker image, you get a nginx server set up as a reverse proxy for your other containers with no config to maintain.
Just run your other containers with the VIRTUAL_HOST environment variable and nginx-proxy will discover their ip:port and update the nginx config for you.
Let say your DNS is set up so that *.test.local maps to the IP address of your Docker host, then just start the following containers to get a quick demo running:
# start the reverse proxy
docker run -d -p 80:80 -v /var/run/docker.sock:/tmp/docker.sock jwilder/nginx-proxy
# start a first container for http://tutum.test.local
docker run -d -e "VIRTUAL_HOST=tutum.test.local" tutum/hello-world
# start a second container for http://deis.test.local
docker run -d -e "VIRTUAL_HOST=deis.test.local" deis/helloworld
Using Traefik
When running a Traefik container, you get a reverse proxy server set up which will reconfigure its forwarding rules given docker labels found on your containers.
Let say your DNS is set up so that *.test.local maps to the IP address of your Docker host, then just start the following containers to get a quick demo running:
# start the reverse proxy
docker run --rm -it -p 80:80 -v /var/run/docker.sock:/var/run/docker.sock traefik:1.7 --docker
# start a first container for http://tutum.test.local
docker run -d -l "traefik.frontend.rule=Host:tutum.test.local" tutum/hello-world
# start a second container for http://deis.test.local
docker run -d -l "traefik.frontend.rule=Host:deis.test.local" deis/helloworld
Here are two possible answers: (1) setup ports directly with Docker and use Nginx/Apache to proxy the vhosts, or (2) use Dokku to manage ports and vhosts for you (which is how I learned to do Method 1).
Method 1a (directly assign ports with docker)
Step 1: Setup nginx.conf or Apache on the host, with the desired port number assignments. This web server, running on the host, will do the vhost proxying. There's nothing special about this with regard to Docker - it is normal vhost hosting. The special part comes next, in Step 2, to make Docker use the correct host port number.
Step 2: Force port number assignments in Docker with "-p" to set Docker's port mappings, and "-e" to set custom environment variables within Docker, as follows:
port=12345 # <-- the vhost port setting used in nginx/apache
IMAGE=myapps/container-1
id=$(docker run -d -p :$port -e PORT=$port $IMAGE)
# -p :$port will establish a mapping of 12345->12345 from outside docker to
# inside of docker.
# Then, the application must observe the PORT environment variable
# to launch itself on that port; This is set by -e PORT=$port.
# Additional goodies:
echo $id # <-- the running id of your container
echo $id > /app/files/CONTAINER # <-- remember Docker id for this instance
docker ps # <-- check that the app is running
docker logs $id # <-- look at the output of the running instance
docker kill $id # <-- to kill the app
Method 1b Hard-coded application port
...if you're application uses a hardcoded port, for example port 5000 (i.e. cannot be configured via PORT environment variable, as in Method 1a), then it can be hardcoded through Docker like this:
publicPort=12345
id=$(docker run -d -p $publicPort:5000 $IMAGE)
# -p $publicPort:5000 will map port 12345 outside of Docker to port 5000 inside
# of Docker. Therefore, nginx/apache must be configured to vhost proxy to 12345,
# and the application within Docker must be listening on 5000.
Method 2 (let Dokku figure out the ports)
At the moment, a pretty good option for managing Docker vhosts is Dokku. An upcoming option may be to use Flynn, but as of right now Flynn is just getting started and not quite ready. Therefore we go with Dokku for now: After following the Dokku install instructions, for a single domain, enable vhosts by creating the "VHOST" file:
echo yourdomain.com > /home/git/VHOST
# in your case: echo foo > /home/git/VHOST
Now, when an app is pushed via SSH to Dokku (see Dokku docs for how to do this), Dokku will look at the VHOST file and for the particular app pushed (let's say you pushed "container-1"), it will generate the following file:
/home/git/container-1/nginx.conf
And it will have the following contents:
upstream container-1 { server 127.0.0.1:49162; }
server {
listen 80;
server_name container-1.yourdomain.com;
location / {
proxy_pass http://container-1;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
proxy_set_header Host $http_host;
proxy_set_header X-Forwarded-For $remote_addr;
}
}
When the server is rebooted, Dokku will ensure that Docker starts the application with the port mapped to its initially deployed port (49162 here), rather than getting assigned randomly another port. To achieve this deterministic assignment, Dokku saves the initially assigned port into /home/git/container-1/PORT and on the next launch it sets the PORT environment to this value, and also maps Docker's port assignments to be this port on both the host-side and the app-side. This is opposed to the first launch, when Dokku will set PORT=5000 and then figure out whatever random port Dokku maps on the VPS side to 5000 on the app side. It's round about (and might even change in the future), but it works!
The way VHOST works, under the hood, is: upon doing a git push of the app via SSH, Dokku will execute hooks that live in /var/lib/dokku/plugins/nginx-vhosts. These hooks are also located in the Dokku source code here and are responsible for writing the nginx.conf files with the correct vhost settings. If you don't have this directory under /var/lib/dokku, then try running dokku plugins-install.
With docker, you want the internal ips to remain normal (e.g. 80) and figure out how to wire up the random ports.
One way to handle them, is with a reverse proxy like hipache. Point your dns at it, and then you can reconfigure the proxy as your containers come up and down. Take a look at http://txt.fliglio.com/2013/09/protyping-web-stuff-with-docker/ to see how this could work.
If you're looking for something more robust, you may want to take a look at "service discovery." (a look at service discovery with docker: http://txt.fliglio.com/2013/12/service-discovery-with-docker-docker-links-and-beyond/)