I have a NAS where I am running various web apps in docker containers through docker-compose. I want some of these web apps to be accessible through the internet, not only when I am connected to my home network.
The problem I'm currently facing is that while cloudflare is able to expose the default web apps (default NAS management 192.168.1.135:80 can be mapped to subdomain.domain.com, for instance), it is unable to expose any docker container I try to run (192.168.1.135:4444 cannot be mapped to subdomain2.domain.com), and I receive a 502 bad gateway error with every app I have tried so far.
The configuration shouldn't be the issue, and it's definitely not the NoTLSVerify flag because the apps run on HTTP and I have configured it that way, so I am out of options to know what is going on and how to solve it.
Looks like the apps you're running on your NAS are proxied through the docker runtime. Consequently, the IP:port you need to add to the cloudflare tunnel config is the one that is reachable from the Host (not the IP of the host itself).
If the host is 192.168.1.135, you need to know which the the IP (internal to the docker network) of the app that you want to access from the outside, typically in the 172.0.0.1/24 range.
Example: If the containers running the apps you want to access are running on 172.0.0.2:4444 for app1 and 172.0.0.3:5555 for app2, the cloudflare config would look like this:
tunnel: the_ID_of_the_tunnel
credentials-file: /root/.cloudflared/the_ID_of_the_tunnel.json
ingress:
- hostname: yourapp1.example.com
service: http://172.0.0.2:4444
- hostname: ypurapp2.example.com
service: http://172.0.0.3:5555
- service: http_status:404
See more details and a video here: How to redirect subdomain to port (docker)
Turns out the problem is due to how docker works with networks, not with how Cloudflare accesses them. I first had to create a network that connected both containers, since adding cloudflare to my docker-compose file didn't work for some reason.
Create a docker network docker network create tunnel
Run docker without specifying the network docker run -d --name cloudflare cloudflare/cloudflared:latest tunnel --no-autoupdate run --token
Add the docker to the network docker network connect tunnel cloudflare
Run the container (note the container should have, as you specified, the network name identical to the one you created earlier, but cloudflare should not be in your docker-compose file) docker-compose up
In the cloudflare tunnel config, you will have to specify the docker internal address of your container (as #lu4t suggested). You can identify the address with docker inspect -f '{{range.NetworkSettings.Networks}}{{.IPAddress}}{{end}}' container
Related
I deployed a ghost blogging platform on my server using docker. Now I want to expose it to the internet but I'm having some difficulties doing so.
I opened port 8000 in my router a forwarded it to port 32769 which is the one assign to that container. Using port 32769 inside my network I can access the website fine but when I try to access it from the internet it gives a took too long to respond error.
Local IP + PORT: http://10.0.0.140:32769/
Docker port config
Port tester
Router settings
This post was also added to Super User since it has been said that it would be responded better in there.
Let's say your application inside docker is now working on port 8000
You want to expose your application to internet.
The request would go: internet -> router -> physical computer (host machine) -> docker.
You need to export your application to your host machine, this could be done via EXPOSE 8000 instruction in Dockerfile.
That port should be accessible from your host machine first, so, when starting your docker image as docker container, you should add -p parameter, such as
sudo docker run -d -it -p 8000:8000 --name docker_contaier_name docker_image_name
From now on, your docker application can be access within your host machine, let's say it is your physical computer.
Forward port from your router to your host machine
This time, you may want to do as what you did in your question.
Access your application from internet.
If I am thinking correctly, the ip address 10.0.0.140 is just your computer LAN IP address, it cannot accessible from internet.
You can only able to connect to your app via an internet IP, to do that, you can check your router to see what is your WAN IP address, which will be assigned to your router by your internet service provider. Or go google with "what is my IP"
What works for me, more or less, is setting up Apache2 as reverse proxy, redirecting a path in Apache2 to the port of the Docker container. This probably could also be done for example with NGINX.
This way the traffic from the net gets proxied to the container and back to the net, and I see the WordPress site. So regarding the question of OP, the docker container is now exposed to the internet.
However 1: This still doesn't explain why I don't get return traffic from the Docker container if I access it directly from the net.
However 2: Not all the url's in the WordPress site are correct, but that seems to be a WordPress issue and not a Docker / routing issue.
I'm using docker for building both UI and some backend microservices, and using Spring Zuul as the Proxy to pass Restful API calls from UI to the downstream microservices. My UI project needs to specify an IP address in the JS file before the build, and the Zuul project also needs to specify the IP addresses for the downstream microservices. So that after starting the containers, I can access my application using my docker machine IP http://192.168.10.1/myapp and the restful API calls in the browser network tab will be http://192.168.10.1/mymicroservices/getProduct, etc.
I can set all the IPs to my docker machine IP and build them without issues. However for my colleagues located in other countries, their docker machine IP will be different. How can I make docker use a specific IP, for example, 192.168.10.50, which I can set in the UI project and Zuul Proxy project, so that the docker IP will be the same for everyone, regardless of what their actual docker machine IP is?
What I've tried:
I've tried port forwarding in VirtualBox. It works for the UI, however the restful API calls failed.
I also tried the solution mentioned in this post:
Assign static IP to Docker container
However I can't access the services from the browser using the container IP address.
Do you have any better ideas? Thank you!
first of to clarify couple things,
If you are doin docker run ..... then you just starting container in your docker which is installed on the host machine. And there now way docker can change ip of your host machine. Thus if your other services are running somewhere else they will have to know something about docker host machine, ip or dns name.
so basically docker does runs on 127.0.0.1 if you are trying it on docker host machine, or on host machine IP if from outside of it. So docker don't need IP of host to start.
The other thing is if you are doing docker-composer up/start. Which means all services are in that docker compose file. In this case docker composer creates docker network for all containers in it. in this case you definitely can use fixed IPs for containers, though most often you don't need to because docker takes care of name resolution in that network.
if you are doing k8s way - then it is third way (production way), and it os another story.
if that is neither of above then please provide more info on how are you doing stuff.
EDIT - to:
if you are using docker composer and need to expose any of your containers to host machine you can do it through port mapping:
web:
image: some image here
ports:
- 8181:8080
left is the host machine port, right is container port
and then in browser on the host you can do request to localhost:8181
here is doc
https://docs.docker.com/compose/compose-file/#ports
I'm using a Digital Ocean docker droplet and have 3 docker containers: 1 for front-end, 1 for back-end and 1 for other tools with different dependencies, let's call it back-end 2.
The front-end calls the back-end 1, the back-end 1 in turn calls the back-end 2. The back-end 2 container exposes a gRPC service over port 50051. Locally, by running the following command, I was able to identify the docker service to be running with the IP 127.17.0.1:
docker network inspect bridge --format='{{json .IPAM.Config}}'
Therefore, I understand that my gRPC server is accessible from the following url 127.17.0.1:50051 within the server.
Unfortunately, the gRPC server refuses connections when running from the docker droplet while it works perfectly well when running locally.
Any idea what may be different?
You should generally set up a Docker private network to communicate between containers using their container names; see e.g. How to communicate between Docker containers via "hostname". The Docker-internal IP addresses are subject to change if you delete and recreate a container and aren't reachable from off-host, and trying to find them generally isn't a best practice.
172.17.0.0/16 is a typical default for the Docker-internal IP network (127.0.0.0/8 is the reserved IPv4 loopback network) and it looks like you might have typoed the address you got from docker network inspect.
Try docker run with following command:
docker run -d -p {server ip}:12345 {back-end 2 image}
It will expose IP port to docker container and will be accessible from other servers.
Note: also check firewall rules, if firewall is blocking access.
You could run docker binding to ip and port as shown by Aakash. Please restrict access to this specific IP and port to be accessed only from the other docker IP and port - this will help to run docker private and doesn't allow other (even the other docker/instances within your network).
Context:
I have a web server hosting a UI from which users can request for emulator instances for my product. Each emulator instance is a webapp running on nodejs. When a user requests an emulator instance from the UI, I spawn a docker container. I would like to return to the user an IP address(+port) from which this emulator container can be accessed.
Note: Presently, docker and the webserver facing the user are running on the same system.
Problems:
1) The default container on the docker0 network is accessible only with it's local IP address on the host. e.g. http://172.17.0.5. I can't access the container with http://localhost:32768 (container was started with -P and was assigned the port 32768). I get a message that the site can't be reached.
2) I can't use the docker host network driver because the emulator uses ports internally which I don't want to expose in the host network
3) I don't want to use the macvlan driver because I will be using up too many IPs.
Is it possibly to map various ports on the host to IPs on the docker0 subnet? If yes, how do I go about this? If this is possible I could expose the host IP and the container specific port to the user.
What is best way to give users access to the containers?
How about a nginx container acting as a proxy? Make your containers have same name always.
Serve new app instance:
docker run -d --rm --name=static_prefix__unique_id your_image
Have a wildcard domain:
unique_id.yourdomain.com
Or simply:
yourdomain.com/unique_id
You can dynamically proxy the request (I assume you're using port 3000 for the nodejs app):
proxy_pass http://static_prefix__$extractedNameFromRequestUri:3000
Docker will do the hard job for you and route traffic from outside to the static_prefix__unique_id container.
An application server is running as one Docker container and database running in another container. IP address of the database server is obtained as:
sudo docker inspect -f '{{ .NetworkSettings.IPAddress }}' db
Setting up JDBC resource in the application server to point to the database gives "java.net.ConnectException".
Linking containers is not an option since that only works on the same host.
How do I ensure that IP address of the database container is visible to the application server container?
If you want private networking between docker containers on remote hosts you can use weave to setup an overlay network between docker containers. If you don't need a private network just expose the ports using the -p switch and configure the addresses of the host machine as the destination IP in the required docker container.
One simple way to solve this would be using Weave. It allows you to create many application-specific networks that can span multiple hosts as well as datacenters. It also has a very neat DNS-based service discovery mechanism.
I should disclaim, I am one of Weave engineering team.
Linking containers is not an option since that only works on the same host.
So are you saying your application is a container running on docker server 1 and your db is a container on docker server 2? If so, you treat it like ordinary remote hosts. Your DB port needs to be exposed on docker server 2 and that IP:port needs to be configured into your application server, typically via environment variables.
The per host docker subnetwork is a Private Network. It's perhaps possible to have this address be routable, but it would be much pain. And it's further complicated because container IP's are not static.
What you need to do is publish the ports/services up to the host (via PORT in dockerfile and -p in your docker run) Then you just do host->host. You can resolve hosts by IP, Environment Variables, or good old DNS.
Few things were missing that were not allowing the cross-container communication:
WildFly was not bound to 0.0.0.0 and thus was only accepting requests on eht0. This was fixed using "-b 0.0.0.0".
Firewall was not allowing the containers to communication. This was removed using "systemctl stop firewall; systemctl disable firewall"
Virtual Box image required a Host-only adapter
After this, the containers are able to communicate. Complete details are available at:
http://blog.arungupta.me/2014/12/wildfly-javaee7-mysql-link-two-docker-container-techtip65/