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.
Related
I have multiple upstream servers from an nginx load balancer:
upstream app {
# Make each client IP address stick to the same server
# See http://nginx.org/en/docs/http/load_balancing.html
ip_hash;
# Use IP addresses: see recommendation at https://www.nginx.com/resources/wiki/start/topics/tutorials/config_pitfalls/
server 1.1.1.1:6666; # app-server-a
server 2.2.2.2:6666; # app-server-a
}
Right now I ue the servers in an active/passove configuration by taking down each servers (eg systemctl myapp stop) then letting nginx detect the server is down.
However I'd like to be able to change the upstream server dyamically, without having to take either app server or nginx OSS down. I'm aware of the proprietary upstream_conf module for nginx Plus but am using nginx OSS.
How can I dynamically dynamically reconfigure the upstream server on nginx OSS?
You can use:
openresty an OSS nginx bundle with lua scripting ability
nginx with lua scripting (you can configure it by yourself using nginx OSS and luajit) to achieve this.
dynx can achieve exactly what you are looking for, it's still work in progress but the dynamic upstream functionality is there and it's configurable through a rest API.
I'm adding the details on how to deploy and configure dynx:
you need to have a docker swarm up and running (for testing purpose
you can have a 1 swarm machine), follow the docker documentation to do that.
after you need to deploy the stack, for example, with this command (you need to be on the dynx git root):
docker stack deploy -c docker-compose.yml dynx
To check if the application deployed correctly, you can use this command:
docker stack services dynx
To configure an location you can use through the api you can for instance do:
curl -v "http://localhost:8888/configure?location=/httpbin&upstream=http://www.httpbin.org/anything&ttl=10"
To test if it works:
curl -v http://localhost:8666/httpbin
Do not hesitate to contact me or open an issue on github if you are not able to get it to work
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!
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.
Is there a way to disable the default EXPOSE 80 443 instruction in the nginx docker file without creating my own image?
I'm using Docker Nginx image and trying to expose only port 443 in the following way:
docker run -itd --name=nginx-test --publish=443:443 nginx
But I can see using docker ps -a that the container exposes port 80 as well:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
ddc0bca08acc nginx "nginx -g 'daemon off" 17 seconds ago Up 16 seconds 80/tcp, 0.0.0.0:443->443/tcp nginx-test
How can I disable it?
The expose instruction is in the docker file which the image is built from.
You need to create your own customized Image for that.
To get the job done:
First locate the dockerfile for the official nginx (library)
Then Edit the dockerfile's expose instruction to 443 only.
Now build your own image modified image using official(customized) dockerfile.
To answer your edited question:
Docker uses iptables, While you could manually update the firewall rules to make the service unavailable at a certain port, you would not be able to unbind the Docker proxy. So port 80 will still be consumed on the docker host and docker proxy.
according to nginx docker image configuration , you can set this before container starts passing an environment var like :
docker run -itd -e NGINX_PORT=443 --name=nginx-test nginx
see :
using environment variables in nginx configuration
then in your nginx you can set :
listen ${NGINX_PORT};
There is a workaround to free the port (but not to unexpose it). I tried avoiding to publish the port but it didn't work and I got errors about the por being already in use anyway. Until I found that the trick is to publish the exposed port but mapped to a different one.
Let me explain with an example.
This will still try to use port 80:
docker up -p 443:443
But this will use 443 and some other random port you pick
docker up -p 443:443 -p<some free port>:80
You can do this in your commands, docker-compose or ansible playbooks to be able to start more than one instance on the same machine. (ie: nginx, which exposes port 80 by default)
I do this from docker-compose and ansible too.
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.