Thanks in advance. I have installed docker in windows and calling the container from localhost. I just using port forwarding in virtual box to specify the port. It's working fine. But I need to access entire ports in my local without specification inside the virtual box. Is there any solution?
When you create a container, you can bind the "internal" port (the one which is EXPOSEd, 80 for an Apache for example) to the "public" one. You have to specify it in your docker run command or in your docker-compose (PORT
If you can reach each container using the IP (or domain name) and the port (ip.of.the.vm:public_port)
You don't have to bind a port in virtual box.
Related
Context, I'm currently dockerizing an application in windows containers, the application
will connect to a Sql Server database from outside the container, normally working with linux containers I could use host driver, but since that is not available in windows containers. How could I connect to that database outside my windows container?
So, the answers provided before are all valid. I'd just add that while Host network is not available on Windows, you can still use the same concept - albeit a bit different.
The native network driver on Windows is Network Address Translation. With that driver, the container will get a private IP address and the ports from the container host can be mapped to the ports on the container, by use of the docker run -p 8080:80, for example.
That way, if you want to continue to use the option to call the localhost between the app container and the database container you can. You just need to specify the port: localhost:8080. Note that if the host is not using that port, you can even map it directly, such as: docker run -p 80:80. The caveat here is: The container host cannot be using the port already, and you can't map the same port to another container. So, if you need another instance, you can map to something like: docker run -p 81:80.
I blogged about this here: https://cda.ms/4nB
I have Ubuntu server 20.04 running as a guest vm. On it I have installed Rancher within a docker container, and mapped port 443 to 9091 to have access to the Rancher UI at 192.168.0.50:9091. Within Rancher I have deployed a nextcloud instance on the local cluster and forwarded the nextcloud port 443 to port 9700 using HostPort. The link generated for the pod is taking me to 172.17.0.2:9700, which I am assuming is the internal Ip for the local node within the cluster.
How can I access the nextcloud container with a browser?
Currently I cannot access it if I simply navigate to the :9700. Is there a way to access the node with the IP I use for my vm?
Thanks
The publish the container port field in the Port Mapping is the one where you specify the the port that container listen to.
It relates directly to containerPort in kubernetes yaml file. Exposing a port in this field gives the system additional information about the network connections a container uses but this field is primarily informational. Not specyfing a port here does not prevent that port from being expose. Any port which is listening on the default "0.0.0.0" address inside a container will be accessible from the network.
I checked the nextcloud image specs and it looks like it the apache-image is listening on port 80 and fpm-image uses 9000.
For more reading please visit rancher document how to expose workloads.
I'm looking for a way to access containers that are running on server in our company lan by domain names. By far I only managed to access them by IPs
So the setup is. Docker (for windows) is running on server srv1.ourdomain.com (Windows Server 2019), network for container is configured with l2bridge driver, container's dns name, as specifiedn in run command, is cont1. It is accessible by dns name on the docker host (srv1) and by IP from my machine.
What can I do to access the container by dns name cont1.ourdomain.com from my local machine located in the same lan?
I tried to use proxy (traefik) but it cant rewrite urls in the content, so web applications running inside the container are failing. Bacause of this I can't host multiple web application behind that proxy.
I know that it is possible to map container's port to host port and then it will be accessible from lan through the host name and host port, but applications I'm running are requiring many ports to be mapped (like 8 ports for each container) and with those containers being short-lived developer's environments it will be a hell to find a port pool when running new container.
So again if I can access container and its' ports by IP, is there a way to do the same by DNS name?
UPD1. Container host is a virtual server running on vmware. I tried to follow those recommendations and configure promiscuous mode. Thise doesn't help with dns though.
UPD2. I tried transparent network as well. For some reason DHCP can never assign propper IP and container ends up with autoconfigured ip from 168.x.x.x subnet.
You could create a transparent network and make the container discoverable on the network just like host. However, using host ports is what's recommended.
Did you try PathStrip or PathPrefixStrip with Traefik? That should let you rewrite the URLs for the backend.
I am using Docker desktop, I have a couple of docker containers running using docker-compose and port forwarding. I can access the containers from my mac using localhost. On the second container, I am exposing on different ports. I can see ip addresses are associated to both containers by using docker inspect, but I cannot access using the ip address.
I would like access the container from my local mac by
dns domain
ip address
Any help appreciated.
Thanks
You cannot directly connect to the container-private IP addresses on MacOS. You also can't connect to them using a VM-based Docker implementation like Docker Toolbox or Kubernetes' minikube, or from a different host. Looking up and using these IP addresses, or trying to manually set them, usually isn't a best practice.
Instead you can use the docker run -p option to publish a port from your container to the host. Programs running directly on the host can access the container using localhost as a host name and the published port number. This works on all platforms; on VM-based solutions use the VM's IP address instead of localhost; from a different host, use the Docker host's DNS name or IP address.
I am having difficulty connecting from the host to an ASP.Net website running in a Windows container on Docker. I can connect to a website running in a Linux container without any problem.
I have tried connecting to both localhost and to the IP port assigned to the container but in both cases I just get a timeout error.
I have tried several ASP.Net examples which are already pre-built along with trying to build my own custom image. In every case I get the same timeout error. I have also tried uninstalling and re-installing docker but that didn't change anything.
I am running Windows 10 Pro and Docker Community Edition Version 17.03.1-ce-win12 (12058)
Ultimately I was able to completely reset my container network using a customized older version of the Microsoft Vitualization cleanup scripts. https://github.com/Microsoft/Virtualization-Documentation/tree/live/windows-server-container-tools/CleanupContainerHostNetworking This reset my container network and everything is now working as expected.
SUMMARY:
When the published port/s for a container are defined using the EXPOSE directive in the container's Dockerfile, the -P argument must be used with the docker run command in order to "activate" those exposed port/s.
It is not possible for a Windows container host to access containers that it is running using localhost, 127.0.0.1 or its external host IP address. Access containers running on a given host, A, by using the IP address of A from a second host, B. Alternatively, you can use the IP address of a container directly.
FULL EXPLANATION:
So there are a few nuances with ensuring that the proper firewall rules are created, and your containers are actually accessible on their published port/s.
For instance, I'll assume that your ASP.Net containerized application is defined by a container image, which was defined by a Dockerfile. If so, you probably defined the published port for the image/app using the Dockerfile EXPOSE directive. In this case, when you actually run the container you need to "activate" that published port using the "-P" argument to the docker run command.
For example, if your container image is web_app, and the Dockerfile for that image included the line, EXPOSE 80, then when you go ahead and run that image you need to do something like:
C:\> docker run -P web_app
Once the container is running, it should be available on container port 80. You can then go ahead and view the app via browser. To do that you have two options:
You can access the app from your container host, using the container IP and port
Find the container IP using docker network inspect nat, then looking for the endpoint/IP address that corresponds with your container.
You can also fund the container IP by running docker exec <CONTAINER ID> ipconfig, where <CONTAINER ID> is the ID of your container.
You can get the ID of your container and the exposed port for your container by running docker ps on the container host.
You can access the app from another host machine, using the container host IP and host port
You can find the IP address of your host using ipconfig.
You can identify the host port upon which your app is exposed, by running docker ps from the host. Then, under PORTS you'll see a mapping of the form 0.0.0.0:<HOST PORT>-><CONTAINER PORT>/TCP. In this mapping <HOST PORT>, is the port upon which your app is available on the host.
Once you have the IP address of your container host, and the port upon which your app is available on the host, you can use that information to access your app from a browser on a separate host.
NOTE: Today you cannot access a container in this way from its own host--currently a Windows container host cannot access the containers it is running, despite whether localhost, 127.0.0.1 or the host IP address is used.