I am attempting to run my ASP.NET Core 1.1 web API in a Docker container, but I cannot connect to the web API from a browser or curl. To troubleshoot, I have also brought up standard nginx and Apache httpd containers and cannot connect to these either, so I believe this is a Docker/Docker Toolbox/configuration issue rather than a problem with my application.
I'll focus on what I have done with nginx and Apache:
I am running Docker Toolbox on Windows 7 Professional, and everything seems to work as I would expect.
Docker commands all work as expected
I can access the underlying Windows filesystem
I can get the expected results from curl http://localhost (if I start the default IIS website on Windows 7)
So now I shut down IIS and run nginx in a container:
$ docker run -d -p 80:80 nginx
45bb1f373c11b820d8431de3eb3bf222d57d412de53e8625f461b62c4279e644
Docker now shows nginx running:
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
45bb1f373c11 nginx "nginx -g 'daemon off" 47 seconds ago Up 48 seconds 0.0.0.0:80->80/tcp, 443/tcp admiring_pike
But I cannot connect with either curl (within the Docker Toolbox command prompt) or a web browser in Windows:
$ curl http://localhost
curl: (7) Failed to connect to localhost port 80: Connection refused
I get exactly the same results if I run an Apache 2.4 (httpd) container.
Any ideas? Thanks! Peter
I have found the answer in another question here.
Because Docker Toolbox is running on a lightweight Linux VM, it has its own IP address. One needs either to map localhost to the VM using DOCKER_HOST ir access the VM via it's IP address, found using the command:
docker-machine ip default
As you are running on VM, you need to follow this docker document from here.
After that run the following command to check the IP address of your VM.
docker-machine ip default
Start the nginx and hit [ip default address]:port in the browser. It works!
Related
I have docker for windows running windows container. Machine is connected to corporate network via Cisco AnyConnect VPN. We have been having this issue for sometime with no solutions. To explain the problem here is an example. Go to docker image here https://hub.docker.com/_/microsoft-dotnet-samples and run the below commands in command prompt / powershell in sequence
docker pull mcr.microsoft.com/dotnet/samples:aspnetapp
docker run -it --rm -p 8000:80 --name aspnetcore_sample mcr.microsoft.com/dotnet/samples:aspnetapp
replace port 8000 with something else if there is an error in lines of hns file being used. Go to browser and do http://localhost:8000 assuming its running on port 8000. It doesn't connect for me. Instead of localhost i also tried below command to find the ipaddress of the container running the image and then replace localhost with that ip address but with same response unable to connect.
docker inspect -f '{{range.NetworkSettings.Networks}}{{.IPAddress}}{{end}}' container_name_or_id
here is an screenshot of the network adapter docker sets up by default
here is another screenshot of the nat network adapter
I have installed docker engine v1.12.3 on Ubuntu 14.04 LTS and since after the following changes to enable Remote API, I'm not able to pull or run any of the docker images,
Added DOCKER_OPTS="-H tcp://127.0.0.1:2375" in /etc/default/docker.
/etc/init.d/docker start.
Following is the error received,
docker: Cannot connect to the Docker daemon. Is the docker daemon running on this host?
Note: I have added login in user to the docker group
If you configure the docker daemon to listen to a TCP socket (as you do), you should use the -H command line option with the docker command to point it to that socket instead of the default Unix socket.
#mustaccio is correct. The docker command defaults to using a unix socket normally at /var/run/docker.sock. You can either make your options setup like:
DOCKER_OPTS="-H tcp://127.0.0.1:2375" -H unix:///var/run/docker.sock" and restart, or always use docker -H tcp://127.0.0.1:2375 whenever you interact with the host from the command line.
The only good scenario I've seen for removing the socket is pure user security. If your Docker host is TLS enabled, you can ensure only authorized people are accessing the host by signed certificates, not just people with access to the system.
I'm running an nginx container on a windows 10 machine. I've stripped it down to a bare minimum - an nginx image provided in the Docker hub. I'm running it using:
docker run --name ng -d -P nginx
This is the output of docker ps:
b5411ff47ca6 nginx "nginx -g 'daemon off" 22 seconds ago Up 21 seconds 0.0.0.0:32771->80/tcp, 0.0.0.0:32770->443/tcp ng
And this is the IP I'm getting when doing docker inspect ng: "IPAddress": "172.17.0.2"
So, the next thing I'm trying to do is access the Nginx server from the host machine by opening http://172.17.0.2:32771 in browser of the host machine. This is not working (host not found etc).
Please advise
On windows, you are using Docker Toolbox, and the IP you need is 192.168.99.100 (which is the IP of the Docker Toolbox VM). The IP you got is the IP of the container inside the VM, which is not accessible directly from Windows.
Follow this article... https://docs.docker.com/get-started/part2/#run-the-app
And make sure your application is running not just docker.
docker run -d -p 4000:80 friendlyhello
After this on Windows 10 host machine
Worked http://192.168.99.100:4000/
Not working: http://localhost:4000/
I used the following command to map the internal port 80 on the running container to port 82 off localhost:
docker run --name webserver2 -d -p 82:80 nginx
accessing nginx image off localhost:82 works great.
The port you want to access from your local web browser is the first number before the :80 which is where nginx image runs virtually in the container.
There is lots of miscommunication out there on the issue -- it's a simple port mapping between the host machine (Windows you are running) and the container running on docker.
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 a running nginx container: # docker run --name mynginx1 -P -d nginx;
And got its PORT info by docker ps: 0.0.0.0:32769->80/tcp, 0.0.0.0:32768->443/tcp
Then I could get response from within the container(id: c30991a04b2f):
docker exec -i -t c3099 bash
curl http://localhost => which return the default index.html page content, it works
However, when I make the curl http://localhost:32769 outside of the container, I got this:
curl: (7) failed to connect to localhost port 32769: Connection refused
I am running on a mac with docker version 1.9.0; nginx latest
Does anyone know what cause this? Any help? thank you
If you are On OSX, you are probably using a VirtualBox VM for your docker environment.
Make sure you have forwarded your port 32769 to your actual host (the mac), in order for that port to be visible from localhost.
This is valid for the old boot2docker, or the new docker machine.
VBoxManage controlvm "boot2docker-vm" --natpf1 "tcp-port32769 ,tcp,,32769,,32769"
VBoxManage controlvm "boot2docker-vm" --natpf1 "udp-port32769 ,udp,,32769,,$32769
(controlvm if the VM is running, modifyvm is the VM is stopped)
(replace "boot2docker-vm" b ythe name of your vm: see docker-machine ls)
I would recommend to not use -P, but a static port mapping -p xxx:80 -p yyy:443.
That way, you can do that port forwarding once, using fixed values.
Of course, you can access the VM directly through docker-machine ip vmname
curl http://$(docker-machine ip vmname):32769
Solved.. I misunderstood how docker port mapping works.
Since I'm using mac, the host for nginx container is a VM, 0.0.0.0:32769->80/tcp maps the port 80 of the container to the port 32769 of the VM.
solution:
docker-machine ip vm-name => 192.168.99.xx
curl http://192.168.99.xx:32769
Not exactly answers for your question but spend some time trying to figure out similar thing in context of "why is my docker container not connecting to elastic search localhost:9200" and this was the first S.O. question that pops up, so I hope it helps some other googling person
if you are linking containers together (e.g. docker run --rm --name web2 --link db:db training/webapp env)
... then Dockers adds enviroment variables:
DB_NAME=/web2/db
DB_PORT=tcp://172.17.0.5:5432
DB_PORT_5432_TCP=tcp://172.17.0.5:5432
DB_PORT_5432_TCP_PROTO=tcp
DB_PORT_5432_TCP_PORT=5432
DB_PORT_5432_TCP_ADDR=172.17.0.5
... and also updates your /etc/hosts
# /etc/hosts
#...
172.17.0.9 db
so you can technically connect to ping db
https://docs.docker.com/v1.8/userguide/dockerlinks/
so for elastic search is
# /etc/hosts
# ...
172.17.0.28 elasticsearch f9db83d0dfb5 ecs-awseb-qa-3Pobblecom-env-f7yq6jhmpm-10-elasticsearch-fcbfe5e2b685d0984a00
so wget elasticseach:9200 will work