I'm new to Docker, using Boot2Docker on OSX. After booting it, this message is given:
To connect the Docker client to the Docker daemon, please set
export DOCKER_HOST=tcp://192.168.59.103:2375
Yet even without it, basic Docker commands (eg, docker run hello-world) work fine.
The install instructions aren't very informative:
Note: If you see a message in the terminal that looks something like this:
To connect the Docker client to the Docker daemon, please set:
export DOCKER_HOST=tcp://192.168.59.103:2375
you can safely set the evironment variable as instructed.
Knowing that it's "safe" doesn't say why it's useful.
What I'm not clear on:
What is the docker "client"?
What is the docker "daemon"?
What is the docker "host"? (The Boot2Docker VM itself?)
Ok, I think I got it.
The client is the docker command installed into OS X.
The host is the Boot2Docker VM.
The daemon is a background service running inside Boot2Docker.
This variable tells the client how to connect to the daemon.
When starting Boot2Docker, the terminal window that pops up already has DOCKER_HOST set, so that's why docker commands work. However, to run Docker commands in other terminal windows, you need to set this variable in those windows.
Failing to set it gives a message like this:
$ docker run hello-world
2014/08/11 11:41:42 Post http:///var/run/docker.sock/v1.13/containers/create:
dial unix /var/run/docker.sock: no such file or directory
One way to fix that would be to simply do this:
$ export DOCKER_HOST=tcp://192.168.59.103:2375
But, as pointed out by others, it's better to do this:
$ $(boot2docker shellinit)
$ docker run hello-world
Hello from Docker. [...]
To spell out this possibly non-intuitive Bash command, running boot2docker shellinit returns a set of Bash commands that set environment variables:
export DOCKER_HOST=tcp://192.168.59.103:2376
export DOCKER_CERT_PATH=/Users/ddavison/.boot2docker/certs/boot2docker-vm
export DOCKER_TLS_VERIFY=1
Hence running $(boot2docker shellinit) generates those commands, and then runs them.
Upon investigation, it's also worth noting that when you want to start using docker in a new terminal window, the correct command is:
$(boot2docker shellinit)
I had tested these commands:
>> docker info
Get http:///var/run/docker.sock/v1.15/info: dial unix /var/run/docker.sock: no such file or directory
>> boot2docker shellinit
Writing /Users/ddavison/.boot2docker/certs/boot2docker-vm/ca.pem
Writing /Users/ddavison/.boot2docker/certs/boot2docker-vm/cert.pem
Writing /Users/ddavison/.boot2docker/certs/boot2docker-vm/key.pem
export DOCKER_HOST=tcp://192.168.59.103:2376
export DOCKER_CERT_PATH=/Users/ddavison/.boot2docker/certs/boot2docker-vm
export DOCKER_TLS_VERIFY=1
>> docker info
Get http:///var/run/docker.sock/v1.15/info: dial unix /var/run/docker.sock: no such file or directory
Notice that docker info returned that same error. however.. when using $(boot2docker shellinit)...
>> $(boot2docker init)
Writing /Users/ddavison/.boot2docker/certs/boot2docker-vm/ca.pem
Writing /Users/ddavison/.boot2docker/certs/boot2docker-vm/cert.pem
Writing /Users/ddavison/.boot2docker/certs/boot2docker-vm/key.pem
>> docker info
Containers: 3
...
It points to the docker host! I followed these steps:
$ boot2docker start
Waiting for VM and Docker daemon to start...
..............................
Started.
To connect the Docker client to the Docker daemon, please set:
export DOCKER_HOST=tcp://192.168.59.103:2375
$ export DOCKER_HOST=tcp://192.168.59.103:2375
$ docker run ubuntu:14.04 /bin/echo 'Hello world'
Unable to find image 'ubuntu:14.04' locally
Pulling repository ubuntu
9cbaf023786c: Download complete
511136ea3c5a: Download complete
97fd97495e49: Download complete
2dcbbf65536c: Download complete
6a459d727ebb: Download complete
8f321fc43180: Download complete
03db2b23cf03: Download complete
Hello world
See:
http://docs.docker.com/userguide/dockerizing/
Related
I'm running Docker on Windows ("Docker Toolbox", not "Docker for Windows").
I've built an image with a rails app inside. It works properly on my Mac OS but stucks on production on Windows.
Using Docker 1.12 and docker-machine 0.8.0 on both machines.
When I create a machine and try to run the container from image, I do:
docker run -it myRepo:myTag bash
which opens me a interactive terminal on Mac OS, but Windows 7 and Windows Server 2011 are both responding with:
"Error response from daemon: oci runtime error: exec: "bash":
executable file not found in $PATH."
I use the MINGW64 shell via the Docker Quickstart Terminal but the old cmd.exe returns the same.
Can anybody help me with this issue? I've tried several hours to find a solution but there are too few answers for Windows.
Thank you in advance!
I also use Windows 7 with MINGW64. Here is what I get using nginx as example:
$docker run -it nginx bash
cannot enable tty mode on non tty input
I don't think you can open a tty using MINGW64.
You can try:
$docker run -i nginx bash
ls
bin
...
You will so no prompt or any indication you are inside the container. Just run ls and it should work inside your container.
Another option is to try to use winpty for the tty:
$ winpty docker run -it myRepo:myTag bash
root#644f59e6f818:/#
Have you tried?
$ winpty docker run -it myRepo:myTag /bin/bash
I haven't got the problem you are mentioning but I have seen it before when I was mapping volumes.
If you are mapping volumes using MINGW64, you will need to add an extra / before the local mapping. For example:
docker run -p 8080:80 -v "/$PWD":/var/share/nginx/html nginx
Let me know your findings.
NOTE : I am not using boot2docker
I am trying to enable the docker remote API on my mac. However all the question here are based on using boot2docker. While installing docker on my machine, I followed these steps using the Docker Toolbox and since then I have always used the command bash --login '/Applications/Docker/Docker Quickstart Terminal.app/Contents/Resources/Scripts/start.sh' to start docker in my local machine.
I was trying to follow the steps mentioned here, which state that I have to edit the docker.conf file. However I cannot locate the file at all. Any help will be greatly appreciated.
Your remote API should already be available. docker-machine env default will give you the details.
export DOCKER_TLS_VERIFY="1"
export DOCKER_HOST="tcp://192.168.56.100:2376"
export DOCKER_CERT_PATH="/Users/jimbob/.docker/machine/machines/default"
export DOCKER_MACHINE_NAME="default"
# Run this command to configure your shell:
# eval $(docker-machine env default)
In the end they both use a VirtualBox VM running boot2docker, they are just accessed in different ways.
Any daemon configuration can be done in the /var/lib/boot2docker/profile file if needed.
I want to use a debian Docker container to test something, and by this I mean execute some commands in the debian bash console. I tried downloading the image using docker pull debian and then running it using docker run debian, but I get no output. What am I doing wrong? Shouldn't the docker container stay open until I close it?
You need to explicitly run bash:
docker run -it debian /bin/bash
The -i means "run interactively", and -t means "allocate a pseudo-tty".
A good place to read a bit more is the section Running an interactive shell in the Quickstart documentation.
I'm new to docker.My Operating system is Mac OS.
I follow the step from docker website,
Download the boot2docker and install it.
run the boot2docker
$ boot2docker init
$ boot2docker start
$ docker run hello-world
the result is that :
bash-3.2$ docker run hello-world
An error occurred trying to connect: Post https://192.168.59.103:2376/v1.19/containers/create: x509: certificate is valid for 127.0.0.1, 10.0.2.15, not 192.168.59.103
then i do
$ boot2docker shellinit to display the environment variables
bash-3.2$ boot2docker shellinit
Writing /Users/wangyao/.boot2docker/certs/boot2docker-vm/ca.pem
Writing /Users/wangyao/.boot2docker/certs/boot2docker-vm/cert.pem
Writing /Users/wangyao/.boot2docker/certs/boot2docker-vm/key.pem
Your environment variables are already set correctly.
maybe I think it makes error by not configuring the variables, So I do this
export DOCKER_HOST=tcp://192.168.59.103:2376
export DOCKER_CERT_PATH=/Users/wangyao/.boot2docker/certs/boot2docker-vm
export DOCKER_TLS_VERIFY=1
then I $ boot2docker shellinit, and the result is no different,
Please tell me how to resolve it
I explained how to use Docker Machine instead of boot2docker, if you're interested: Can't run docker on os X with boot2docker.
Because I think Boot2Docker won't be the recommended way of using Docker (on Windows/OS X) any longer soon.
TL;DR
docker-machine create -d virtualbox dev
eval "$(docker-machine env dev)"
docker run hello-world
I'm new to Docker...
From my understanding, Docker is only compatible with Linux, is it possible to run docker for development purposes on a Mac?
I installed virtualbox using homebrew and have tried to create a virtualbox instance. I installed docker, but am having trouble getting my mac to communicate with the vm docker instance. My end goal is to get a locally debuggable instance of tomcat running on the docker container.
Any help or tips would be helpful.
Information:
Because Docker only runs on Linux you will need to install some kind of virtual instance on your local machine. An easy and popular way to do that is to install
Boot2docker and VirtualBox. VirtualBox is a dependency of Boot2docker. You can download, setup and install the latest versions from their websites or if you are using Homebrew, as you mentioned, you can quickly get the working binaries both in one step.
After installing boot2docker, you're ready to use Boot2docker to create a Tomcat Container. You can find a pre-configured tomcat image by searching Docker's community repository, docker hub registry.
Notes:
Each time you execute the docker run command a new container is created.
The VM running Docker requires a ssh private/public encryption key handshake to connect to. If you follow my steps below, one will be generated for you.
Steps to Setup Tomcat using the tomcat image:
Open Terminal and run this command: brew install boot2docker
Create a new Boot2Docker VM instance using the init command: boot2docker init
Run this command in Terminal to forward local ports to the vm:
for i in {10000..10999}; do VBoxManage modifyvm "boot2docker-vm" --natpf1 "tcp-port$i,tcp,,$i,,$i”; VBoxManage modifyvm "boot2docker-vm" --natpf1 "udp-port$i,udp,,$i,,$i";done
Start the boot2docker daemon: boot2docker start or boot2docker up
After starting docker, copy the exports that are displayed from the previous command to your clipboard
Edit your bash profile file ~/.bash_profile (or if you are using zsh, edit the resource configuration file ~/.zshrc) with a text editor (I prefer using Sublime text): subl .zshrc *note: this will permanently save the docker env variables.
Paste the exports into that file and save
Execute the source command on the file: source .zshrc
Pull the latest tomcat image to create a container and start tomcat: docker run -it --rm -p 10080:8080 tomcat:8.0 *note: this will forward your local 10080 port to the vm's 8080 port.
Go to http://localhost:10080, you should see the tomcat start page!
Useful Docker commands:
$ boot2docker status
$ docker version
$ docker ps #shows running containers
$ docker ps -a # shows all containers
$ docker exec -it NAME /bin/bash #to start a bash session on the container. -i = interactive, -t = tty
External Resources:
https://docs.docker.com/installation/mac/#installation
https://registry.hub.docker.com/_/tomcat/
Most people use boot2docker to run on Macs. You may also want to take a look at Kitematic, which gives you a GUI to play with.
Finally, the future is probably to use docker machine, which can provision a VM for you.
Docker requires Linux Kernel features, hence it cannot be run natively on OSX.
See instead Boot2Docker. This link gives you instructions on how to get going.