Docker on Win10 - is it possible to have multiple terminals? - windows

I am new to Docker - installed DockerToolbox on Win10. And managed to run some basic docker examples. But I cannot seem to figure out how to access same container from multiple command line windows.
Quick online search suggested finding container ID (e.g. 2c7e29b9b666) via
docker ps
then running (I presume in new command window)
docker exec -it 2c7e29b9b666 bash
but that does not work in Win10.
Error message received is:
A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.
Edit: in the first window I started docker machine via:
docker-machine create --driver virtualbox tombox
and I can see 'tombox' in second window if I do:
docker-machine ls
Do I need to somehow reference 'tombox' when running docker commands in second window?

Related

Docker Engine not running in Mac M1 series

Problem : I was trying to set up Docker on my Mac M1, docker engine was somehow keep running (it was in kind of hung state). When I tried running docker ps command, I used to get the error "Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?"
Solution: In Docker Desktop go to settings and try these two steps:-
Clean/purge data
Reset to Factory defaults.
Doing this helped me to fix the issue.

docker deamon is not work in windows

I try to run docker in bash ubuntu on windows. But every time I get this message
"Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?". If i run it in powershell - it work. Can somebody help?
Connecting to the docker deamon requires some privilidges that you don't have when starting the bash terminal.
You can however use the docker command terminal which will allow you to interact with the docker deamon.
Found the solution on this post: https://blog.jayway.com/2017/04/19/running-docker-on-bash-on-windows/
Connect Docker on WSL to Docker on Windows
Running docker against an engine on a different machine is actually quite easy, as Docker can expose a TCP endpoint which the CLI can attach to.
This TCP endpoint is turned off by default; to activate it, right-click the Docker icon in your taskbar and choose Settings, and tick the box next to “Expose daemon on tcp://localhost:2375 without TLS”.
With that done, all we need to do is instruct the CLI under Bash to connect to the engine running under Windows instead of to the non-existing engine running under Bash, like this:
$ docker -H tcp://0.0.0.0:2375 images
REPOSITORY TAG IMAGE ID CREATED SIZE
There are two ways to make this permanent – either add an alias for the above command, or better yet, export an environment variable which instructs Docker where to find the host engine:
$ echo "export DOCKER_HOST='tcp://0.0.0.0:2375'" >> ~/.bashrc
$ source ~/.bashrc
Now, running docker commands from Bash works just like they’re supposed to.
$ docker run hello-world
Hello from Docker!This message shows that your installation appears to be working correctly.

How to enable Docker API access from Windows running Docker Toolbox (docker machine)

I am running the latest Docker Toolbox, using latest Oracle VirtualBox, with Windows 7 as a host OS.
I am trying to enable non-TLS access to Docker remote API, so I could use Postman REST client running on Windows and hit docker API running on docker-machine in the VirtualBox. I found that if Docker configuration included -H tcp://0.0.0.0:2375, that would do the trick exposing the API on port 2375 of the docker machine, but for the life of me I can't find where this configuration is stored and can be changed.
I did docker-machine ssh from the Toolbox CLI, and then went and pocked around the /etc/init.d/docker file, but no changes to the file survive docker-machine restart.
I was able to find answer to this question for Ubuntu and OSX, but not for Windows.
#CarlosRafaelRamirez mentioned the right place, but I will add a few details and provide more detailed, step-by-step instructions, because Windows devs are often not fluent in Linux ecosystem.
Disclaimer: following steps make it possible to hit Docker Remote API from Windows host, but please keep in mind two things:
This should not be done in production as it makes Docker machine very not secure.
Current solution disables most of the docker-machine and all docker CLI functionality. docker-machine ssh remains operational, forcing one to SSH into docker machine to access docker commands.
Solution
Now, here are the steps necessary to switch Docker API to non-TLS port. (Docker machine name is assumed to be "default". If your machine name has a different name, you will need to specify it in the commands below.)
Start "Docker Quickstart Terminal". It starts Bash shell and is the place where all following commands will be run. Run docker-machine ip command and note the IP address of the docker host machine. Then do
docker-machine ssh
cd /var/lib/boot2docker
sudo vi profile This starts "vi" editor in elevated privileges mode required for editing "profile" file, where Docker host settings are. (If as a Windows user you are not familiar with vi, here's is super-basic crash course on it. When file is open in the vi, vi is not in editing mode. Press "i" to start edit mode. Now you can make changes. After you made all the changes, hit Esc and then ZZ to save changes and exit vi. If you need to exit vi without saving changes, after Esc please type :q! and hit Enter. ":" turns on vi's command mode, and "q!" command means exit without saving. Detailed vi command info is here.)
Using vi, change DOCKER_HOST to be DOCKER_HOST='-H tcp://0.0.0.0:2375', and set DOCKER_TLS=no. Save changes as described above.
exit to leave SSH session.
docker-machine restart
After doocker machine has restarted, your sould be able to hit docker API URL, like http://dokerMachineIp:2375/containers/json?all=1, and get valid JSON back.
This is the end of steps required to achieve the main goal.
However, if at this point you try to run docker-machine config or docker images, you will see an error message indicating that docker CLI client is trying to get to the Docker through the old port/TLS settings, which is understandable. What was not expected to me though, is that even after I followed all the Getting Started directions, and ran export DOCKER_HOST=tcp://192.168.99.101:2375 and export DOCKER_TLS_VERIFY=0, resulting in
$ env | grep DOCKER
DOCKER_HOST=tcp://192.168.99.101:2375
DOCKER_MACHINE_NAME=default
DOCKER_TLS_VERIFY=0
DOCKER_TOOLBOX_INSTALL_PATH=C:\Program Files\Docker Toolbox
DOCKER_CERT_PATH=C:\Users\USERNAME\.docker\machine\machines\default
the result was the same:
$ docker-machine env
Error checking TLS connection: Error checking and/or regenerating the certs: There was an error validating certificates for host
"192.168.99.101:2376"
If you see a problem with how I changed environment variables to point Docker CLI to the new Docker host address, please comment.
To work around this problem, use docker-machine ssh command and run your docker commands after that.
I encountered the same problem and thanks to #VladH made it working not changing any internal Docker profile properties. All you have to do is correctly define Windows local env variables (or configure maven plugin properties, if you use io.fabric8 docker-maven-plugin).
Note that 2375 port is used for non-TLS connections, and 2376 only for TLS connections.
DOCKER_HOST=tcp://192.168.99.100:2376
DOCKER_TLS_VERIFY=0
DOCKER_TOOLBOX_INSTALL_PATH=C:\Program Files\Docker Toolbox
DOCKER_CERT_PATH=C:\Users\USERNAME\.docker\machine\machines\default

Easiest way to connect with PuTTY to an existing docker container

Often I come across this situation:
I have an existing docker container, running a certain service, usually set up from a Dockerfile from Github, etc., usually based on Ubuntu
I am able to run commands inside this container (with docker exec or by setting an entrypoint), including sh
Interactive commands like vi, nano, aptitude or mc don't work, because of the buggy terminal of Docker Toolbox - with errors ranging from defective arrow keys over garbled characters to plain crashes.
Now the question:
Can I run anything inside my container to connect to a machine with a proper terminal? For example I could SSH into the docker host, so maybe I can run something there that the container can connect to?
I tried mosh, but it seems the mosh client does not run a shell by itself, but instead tries to forward to sshd, which the container doesn't have.
Docker is used to create light weight containers that can run a service with as minimal resources as possible. In addition, docker does not limit what code, apps or utilities you would want to run. That being said, if you are trying to connect to the container as you would to other linux servers, via ssh, you would need to be sure that the docker instance contains and is running an ssh server such as openssh-server and that you expose the port, normally port 22, when you execute the 'docker run' command.

Port forwarding issues trying to run a docker container

I am new to docker and nowhere near a networking expert, but I am seeing some strangeness when trying to run a docker container instance (right word?). I am running docker on OSX and set it up using the documentation found here: http://viget.com/extend/how-to-use-docker-on-os-x-the-missing-guide
Everything seems to have gone along fine, then I set up the port forwarding rules via these lines:
for i in {49000..49900};
do VBoxManage modifyvm "boot2docker-vm" --natpf1 "tcp-port$i,tcp,,$i,,$i";
done
I can confirm the boot2docker VM instance by checking the configuration within the Oracle VM VirtualBox Manager->Network->Adapter 1->Port Forwarding with the OSX.
I then run this command to get the container.
docker run -d -P dockerhub.emory.edu/ecoi_trunk:2
I do a "docker ps" and get this info.
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
f20bfefa2e97 dockerhub.emory.edu/ecoi_trunk:2 "/usr/sbin/apachectl 18 seconds ago Up 15 seconds 0.0.0.0:49153->443/tcp, 0.0.0.0:49154->80/tcp cranky_einstein
However, when I run an "lsof -i :49153" I see nothing is listening. I also can't reach the container via the "l****host:49153" in my browser. It just hangs.
What's strange is if I explicitly set the port (rather than allowing docker to assign one) via the following command:
docker run -d -p 49000:80 dockerhub.emory.edu/ecoi_trunk:2
It seems to work (lsof -i:49000 displays a TCP LISTEN), and I can confirm it's listening and the container is reachable via "l****host:49000". However, it's extremely slow. I'm not sure if either are related, but would welcome any tips or thoughts.

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