Here is my Dockerfile:
FROM ros:kinetic-ros-core-xenial
CMD ["bash"]
If I run docker build -t ros . && docker run -it ros, and then from within the container echo $PATH, I'll get:
/opt/ros/kinetic/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
If I exec into the container (docker exec -it festive_austin bash) and run echo $PATH, I'll get:
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
Why are the environment variables different? How can I get a new bash process on the container with the same initial environment?
The ENTRYPOINT command is only invoked on docker run, not on docker exec.
I assume that this /ros_entrypoint.sh script is responsible for adding stuff to PATH. If so, then you could do something like this for docker exec:
docker exec -it <CONTAINER_ID> /ros_entrypoint.sh bash
docker exec only gets environment variables defined in Dockerfile with instruction ENV. With docker exec [...] bash you additionally get those defined somewhere for bash.
Add this line to your Dockerfile:
ENV PATH=/opt/ros/kinetic/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
or shorter:
ENV PATH=/opt/ros/kinetic/bin:$PATH
This is old question but since it's where google directed me I thought I'll share solution I ended up using.
In your entrypoint script add a section similar to this:
cat >> ~/.bashrc << EOF
export PATH="$PATH"
export OTHER="$OTHER"
EOF
Once you rebuild your image you can exec into your container (notice bash is invoked in interactive mode):
docker run -d --rm --name container-name your_image
docker exec -it container-name /bin/bash -i
If you echo $PATH now it should be the same as what you have set in .bashrc
Related
I have some problems with exporting an environment variable into docker Entrypoint file.
This is my docker file content:
FROM ubuntu:16.04
ADD entrypoint.sh .
RUN chmod 777 entrypoint.sh
ENTRYPOINT ["./entrypoint.sh"]
CMD ["/bin/bash"]
In the Entrypoint file, I try to run command "export TOKEN=$client_token". Then, I create a container with that image file and I run "docker exec -it /bin/bash" command and into the container I continue run "set" command to show all environment variables. So,I can not find the $TOKEN variable that I exported before.
How can I export an environment variable into the entrypoint file?
You must inject your host environment variable (client_token) into the docker container using '-e' when running:
docker run -it --rm -e client_token=<whatever> <your image>
This works for example with this kind of entrypoint:
#!/bin/bash
export TOKEN=$client_token
echo "The TOKEN is: ${TOKEN}"
# do stuff ...
If you don't know the token value when the container was run, you should inject during attachment (docker exec) and perform required operations inside, but probably it is not valid for you if running container already needed that information.
docker exec -it -e TOKEN=<whatever> <your container>
BRs
I have pulled one docker image and docker container is running successfully as well. But I want to run one shell script in the running docker. The shell script is located in my hard disk. I am unable to find out which command to use and how to give pathname of the shell file so that it can be executed in running docker.
Please guide me.
Regards
TL;DR
There are two ways that could work in your case.
You can run one-liner-script using docker exec sh/bash with -c argument:
docker exec -i <your_container_id> sh -c 'sh-command-1 && sh-command-2 && sh-command-n'
You can copy shell script into container using docker cp and then run it in docker context:
docker cp ~/your-shell-script.sh <your_container_id>:/tmp
docker exec -i <your_container_id> /tmp/your-shell-script.sh
Precaution
Not all containers allow to run shell scripts in their context. You can check it executing any shell command in docker:
docker exec -i <your_container_id> echo "Shell works"
For future reference check section Understand how CMD and ENTRYPOINT interact
Docker Exec One-liner
docker exec -i <your_container_id> sh -c 'sh-command-1 && sh-command-2 && sh-command-n'
If your container has sh or bash or BusyBox shell wrapper (such as alpine, you can send one-line shell script to container's shell.
Limitations:
only short scripts;
hard to pass command-line arguments;
only if your container has shell.
Docker Copy and Execute Script
docker cp ~/your-shell-script.sh <your_container_id>:/tmp
docker exec -i <your_container_id> /tmp/your-shell-script.sh -arg1 -arg2
You can copy script from host to container and then execute it.
You can pass arguments to the script.
You can run script with root credentials with -u root: docker exec -i -u root <your_container_id> /tmp/your-shell-script.sh -arg1 -arg2
You can run script interactively with -t: docker exec -it <your_container_id> /tmp/your-shell-script.sh -arg1 -arg2
Limitations:
one more command to execute;
only if your container has shell.
I cannot get a bash shell into an alpine container.
I'm starting with this Alpine container:
gitlab/gitlab-runner:alpine
I'm adding a bash shell and other configs in this dockerfile:
from gitlab/gitlab-runner:alpine
ENV http_proxy=<corporate_proxy>
ENV https_proxy=<corporate_proxy>
RUN apk add vim wget curl nmap lsof bash bash-completion which
CMD ["/bin/bash"]
RUN ls -l /bin # THIS WORKS, I CAN SEE 'BASH' SHOW UP WITH 755 OWNED BY ROOT
RUN which bash # THIS ALSO WORKS
RUN /bin/bash -c "echo hi" # YES, THIS WORKS TOO
However when spawning the container to use a bash shell via:
docker run -idt <image_name> /bin/bash, the container fails to start with FATAL: Command /bin/bash not found.
Note that these other options also fail for me when spawning a container: ash, sh, /bin/ash, /bin/sh, etc
running the container with --user root also does not work.
The entrypoint is a GitLab Runner script. Change it to bash to get shell access:
$ docker run -it --entrypoint /bin/bash <image_name>
It turns out something funky was being set in the container's entrypoint. I need to remember to override the entrypoint when spawning a new container via docker run.
Adding this line in the Dockerfile fixed the problem:
ENTRYPOINT: []
1- verify if you container in fully loaded by :
docker ps
so after to enter in bash shell like:
docker exec -it <<container_name>> bash
Alpine doesn't have bash, use sh instead:
docker exec -it 64103333b32 /bin/sh
I am using Jenkins pipeline to build and deploy a docker container.
What I want to do is to pass Jenkins environment variables to docker container.
See the screenshot.
I defined the environment variables on Jenkins.
I check the docker container environment variables using the following commands
- docker exec -it docker_id bash (get into the docker)
- printenv (print environment variables)
I want to see the Jenkins environment variables in docker container.
Is this possible? If so, please let me know the way to do it.
Thanks in advance!
you can set all your variables in .env file and give it to when docker going to run your container:
TBS_END_POINT=http://192.168.82.2:2020/QWEr
MONGO_HOST=172.17.0.3
MONGO_PORT=27017
REPLICA_SET=replicaset
API_PORT=3001
REDIS_PORT=4432
NODE_ENV=development
then when you want to run you container say:
docker run --env-file .env MyImage
Did you try
docker run -e
https://docs.docker.com/engine/reference/run/#env-environment-variables
$ export today=Wednesday
$ docker run -e "deep=purple" -e today --rm alpine env
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME=d2219b854598
deep=purple
today=Wednesday
HOME=/root
or
$ docker run -d --name tst -e TESTME=YES busybox tail -f /dev/null
55a3fe206588a8030365df30a670ca89a50c54816d044184d5870a4a76ce8199
$ docker exec -it tst sh
/ # echo $TESTME
YES
/ #
Try to run docker-machine env in the Docker terminal to get a list of all the environment variables and their values.
I have got some docker container for instance my_container
I Want to run a long living script in my container, but not killing it while leaving the shell
I would like to do something like that
docker exec -ti my_container /bin/bash
And then
screen -S myScreen
Then
Executing my script in screen and exit the terminal
Unfortunately, I cannot execute screen in docker terminal
this maybe help you.
docker exec -i -t c2ab7ae71ab8 sh -c "exec >/dev/tty 2>/dev/tty </dev/tty && /usr/bin/screen -r nmsrv -s /bin/bash"
and this is the reference link
Only way I can think of is to run your container with your script at the start;
docker run -d --name my_container nginx /etc/init.d/myscript
If you have to run the script directly in an already running container, you can do that with exec:
docker exec my_container /path/to/some_script.sh
or if you wanna run it through Php:
docker exec my_container php /path/to/some_script.php
That said, you typically don't want to run scripts in already running containers, but to just use the same image as some already running container. You can do that with a standard docker run:
docker run -a stdout --rm some_repo/some_image:some_tag php /path/to/some_script.php