Docker uses bash not sh
Docker uses bash not sh. /script. If you want to have an interactive terminal, you want to use docker exec -ti ${container name or id} sh. After successful installation, we can get the installed path of the bash with the help of which command: $ docker run -i -t openjdk:8-jdk-alpine /bin/sh / # which The documentation states. sh to run the start. sh The run_netcat_webserver. It’ll make sure to remove the container when we exit: $ docker exec -it CONTAINER_ID sh. docker exec -it <container_id> /bin/bash RUN entries cannot modify environment variables (I assume you want to set more variables in image_env_setup. The container will run (docker run nginx-healthcheck-broken), but if you type docker ps in another terminal, you'll see it says (unhealthy) under status. docker run -ti --rm test /file. bashrc, of course. I changed default shell into bash by making a new image with below Dockerfile commands. 12' If you are afraid of that long command line, put those commands into a shell script and call the script with RUN: script. The output shows the contents of the root directory inside the $ docker run docker/whalesay bash $ docker ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 7ce600cc9904 docker/whalesay "bash" 5 seconds ago Exited (0) 3 seconds ago loving_mayer But also keep in mind an image may not have bash, and maybe you should try sh or /bin/sh instead. , CMD ["command"]), Docker uses the bash shell instead. /opt/ros/i # Add the Bash aliases cat /usr/sbin/bashrc_alias. When you create a Docker image and instantiate it as a container, the ENTRYPOINT command executes by default. In particular, it does not use the ENTRYPOINT or CMD from the image at all. bashrc. One of these In your docker file you can use the chmod command to set the SUID bit in the su command, located at /file like this RUN chmod u+s /file The u+s option specifies that the SUID bit should be set on the file. Lens (Kubernetes IDE) tries multiple shell commands like this: sh -c 'clear; (bash || ash || sh)' Docker could do something similar, but it would not guarantee that the chosen shel is what you prefer. Docker ENTRYPOINT Explained. If you specify your command as a regular string (e. Then I will discuss what Alpine is. Basically I run following command docker run -d -P --volumes-from=ol7-pgdata --name pgdb1 -h pgdb1 -e DBNAME=PGDB1 -e OPNAME=deploy postgres/pgaas This container should start a which means the process got started when you run docker run ubuntu is /bin/bash, but you're not in an interactive mode and does not allocate a tty to it, so the process exited immediately and the container exited. Most of the time when I use Docker I am using it to package and distribute an application. It is not safe to be root while running the container. I am just posting the comment as an answer so that it is easier for others, having the similar problem, to find it. bashrc or the . 12 && \ nvm use 0. sh ). sh xyz Here, we’ll log in to the container with a basic command line interpreter (/bin/sh). Only ENV entries in the Dockerfile (and docker options like --rcfile can change the environment). You can also decide to source image_env_setup. If you have to, you can arguably use them even in production (which defeats the purpose of increased security - such as hiding environment variables and protecting scripted apps code). sh #!/bin/bash echo $1 Build the image using the existing Dockerfile: docker build -t test . e. 9. sh && ', or you could even go so far as to avoid bashisms (like source) entirely, and instead opt to only ever use valid POSIX equivalents, e. , CMD ["grunt"], a JSON array with double quotes), it will be executed without a shell. You also must set executable permission for start. sh EXPOSE 4555 # Add this line # It _must_ use the JSON-array syntax ENTRYPOINT [". , docker exec -it docker_app_1 bash The problem for me was that running the command conda activate env inside docker after installing caused conda to ask me to use the conda init bash command. Here in this guide, I will first discuss what Docker is. Actually, it’s handy to use the –rm argument when we start a container in interactive mode. sh"] Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; I'm creating an image that has a similar problem like the following docker project: Dockerfile FROM alpine:3. bash_profile file (what ever you prefer). Bash does support environment variables with dots, so the I created a docker image from openjdk:8-jdk-alpine and I want to use bash, rather than sh as my shell, however when I try to execute simple commands I get the following errors: RUN bash. sh In Dockerfile put: set -e sets a shell option to immediately exit if any command being run exits with a non-zero exit code. sh and docker-entrypoint. sh is very simple and it works fine: #!/bin/bash while true ; do nc -l 8080 < index. other commands in the line do not run without -c; sh python would not run, it requires sh -c python. latest bash # docker run -it node:latest bash. the --interactive = -i CLI flag asks to keep STDIN open even if not attached The most voted answer has the correct idea, however, it did not work in my case. Since the command is used to attach/execute into the existing process, therefore it uses the current user there directly. bash -c 'source /script. In case you don't want (or have) a running container, you can call your script directly with the run command. 5. ;-) RUN exit 1 ---> Running in 7c98aab6b52c The command '/bin/sh -c exit 1' returned a non For docker run:. The script will return with the exit code of the failing command. /wait-for-it. Is there any way to manually reconfigure Docker to open /bin/bash? If you are using an Alpine image, you must use #!/bin/sh instead of #!/bin/bash in the first line of your bash file. On Ubuntu, /bin/sh is dash, which is designed to be fast, to use a small amount of memory, and doesn't support much more than the minimum expected from /bin/sh. When your Dockerfile runs RUN . CMD grunt) then the string after CMD will be executed with /bin/sh -c. Next, using the Alpine Package Keeper (apk), we can install bash into the container core utilities. sh file in the PATH, BUT you copied it in / which is not in the PATH. /upload. Improve this answer. E. Just installing sudo weakens security. sh in root /, which does not exist. sh /env. /docker-entrypoint. 12 && nvm alias default 0. /gradlew build. I want to run: docker exec -it <container_name> /bin/bash or. I had to log into the docker container as a root user to install vim. This can be useful for tasks such as running automated tests, deploying applications, or debugging problems. On RHEL, /bin/sh is bash, which is slower and uses more memory but has more features. # make /bin/sh symlink to bash instead of dash: RUN echo "dash dash/sh boolean false" | debconf-set-selections. However, these images often lack the widely-used bash shell, leaving you with the default sh or ash. In older Alpine image versions (pre-2017), Docker images are pretty minimal, but you can install ping in your official ubuntu docker image via:. 12 && nvm use 0. This command creates a new Docker container from the official alpine image. From the bash man page: set -e: Exit immediately if a pipeline (which may consist of a single simple command), a list, or a compound command (see SHELL GRAMMAR 现在我们已经在这个 docker 容器中成功启动了 bash，我们可以在容器中运行各种命令。我们也可以对没有 bash 的容器使用 sh。. I'm creating a Dockerfile build script and would like to use bash commands. sh. Make sure your script is executable (run chmod +x Script. Docker is a tool that is used to encapsulate the application with all its dependencies, called Docker containers. When I try to build the image it successfully references the . Or, like @Maroun's answer in comment, you can change your CMD to execute your bash script. docker run -it --user nobody busybox For docker attach or docker exec:. Q: How do I use docker run bash script? A: To use docker run bash script, you can use the following command: docker Google's distroless images have versions tagged debug, which contain busybox executable (with sh bundled in). / RUN chmod +x . sh #!/bin/bash nvm install 0. CMD ["sh", ". The -it flag combines both -i and -t together — which keeps STDIN open and allocates a pseudo-tty. If you would like to use bash in your Alpine-based Docker containers, this guide will show you how to install and use Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; Don't use alias docker="winpty docker". bashrc It worked a treat! Another option is to just use the "docker exec -it <container-name> command" from outside the container and just use your own . /env. The u refers to the permissions for the owner of the file, and the +s means to add the SUID bit to the file's permissions. sh from the . apt-get update -y apt-get install -y iputils-ping Chances are you don't need ping on your image, and just want to use it for testing purposes. If your script is being run by the sh shell, but you want bash, the proper solution is either to have the sh process invoke bash as a one-off, e. sh >> ~/. ENTRYPOINT serves as the starting point for a Docker container’s runtime process. sh RUN source /env. So when is it sh and when bash?The image I’m providing supports both and I want it to be bash, not sh, however I can’t find a way to By using the CMD, Docker is searching the sayhello. More info on Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; I'm trying to connect to a running container or start a new container in interactive mode with the bash shell -- not the sh shell. FROM <parent image>. sh COPY . The comment from @java25 did the trick in my case. So I have in my docker build folder: Dockerfile index. sh"] CMD ["node", This can appear as if the attach command is hung when in fact the process may simply not be interacting with the terminal at that time. sh instead of letting the shebang This works: docker exec -it my_container sh -c "echo a && echo b" This doesn't work: docker exec -it my_container "echo a && echo b" Options. By default the Docker executor doesn’t override the ENTRYPOINT of a Docker image and passes sh or bash as COMMAND to start a container that runs the job script. Simply remove the sudo from line number 5. Using the --rm flag tells Docker to tidy up You cannot use shell form to specify any command or the docker run command-line arguments while starting the container because the ENTRYPOINT command runs as a subcommand of /bin/sh –c. RUN DEBIAN_FRONTEND=noninteractive dpkg-reconfigure dash. This means that most environment variables will not be present. Run the image with arguments abc or xyz or something else. sh abc docker run -ti --rm test /file. RUN uses /bin/sh by default. Remember that this is a workaround and it should be only used in development environments. 10raw I understand sh -c calls the program sh as the interpeter and executes the script as intrepreted by this command, but what is happening in this case / why does -c cause an issue with the script? E. . docker exec is a debugging command that's not normally part of the "build and run an image" workflow. You need to do any one of these two or both. For that you don't need sudo, because you're root already. What Alpine-based Docker images are known for their small size and security, making them a popular choice among developers. After this, I will walk you through the different steps to install docker run -it --rm --entrypoint /bin/bash vulnerables/web-dvwa OR if you want a shell on the running mysqld container, you can run it normally w/ out -it argument and then do the following to get a bash shell in the running container. To execute the script directly use the exec array form instead: RUN ["/Script. If I select any container and click CLI button, the /bin/sh shell will be opened by default. The RUNcommand within a Dockerfile always uses /bin/sh by I use a Docker container for my development environment and set the shell to bash in my Dockerfile: # ENTRYPOINT ["bash"] Yet when VS Code was connecting to my container it was insisting on using the /bin/ash shell which was driving me crazy However the fix (at least for me) was very simple but not obvious: From the There are multiple programs that implement the language of /bin/sh. docker run -it <container_name> <image_name> /bin/bash and get an interactive bash shell. This -tty tells Docker to create a virtual terminal session within your container. Using sudo inside the docker fails because sudo is not installed, there is no need to use sudo inside the docker because all of the commands inside the docker run as user root. Remove the iterative tty -i -t arguments and use this: $ docker run ubuntu:bionic /bin/bash /path/to/script. sh HealthCheckTest. I use Laradock which consists of multiple containers. In the example above, we use the ‘docker run bash’ command to start a new Docker container and run the ‘ls -l’ command inside it. sh TEST=test123 I built the When using the exec form and executing a shell directly, as in the case for the shell form, it is the shell that is doing the environment variable expansion, not docker. ENTRYPOINT lets you set the container’s primary purpose, like running a web server, I'm trying to write a docker image to run a simple webserver though netcat. html run_netcat_webserver. sh"] . It solves your problem but break pipes. So use an absolute path to the script you want to execute: CMD ["/sayhello. We use the -d flag to detach the container from our terminal and run Nowadays, Alpine images will boot directly into /bin/sh by default, without having to specify a shell to execute: $ sudo docker run -it --rm alpine / # echo $0 /bin/sh This is since the alpine image Dockerfiles now contain a CMD command, that specifies the shell to execute when the container starts: CMD ["/bin/sh"]. Depending on the image, you may also have bash available or if it’s a distroless image, then not @alper It is safe to be root while you're building the container using Dockerfile. RUN . It will depend on the image Bash itself is installed at /usr/local/bin/bash, not /bin/bash, so the recommended shebang is #!/usr/bin/env bash, not #!/bin/bash (or explicitly running your script via bash //script. 12 and make it executable: chmod +x script. log". The executable has a different process ID than the container's 'PID 1'. Use the Use the same file. So CMD executable I have dockerfile wherein I have referenced start. $ winpty docker run -ti ubuntu root@e85cff7d1670:/# exit $ wintpy docker run ubuntu bash HELLO HELLO $ wintpy docker run ubuntu bash HELLO | cat stdout is not a tty Copy this to your . This script uses winpty docker only if -ti is used. Sometimes I'm using it for something cooler like a distributed computing project. On the other hand, Alpine Linux is a lightweight and minimal Linux distribution. In my case, /bin/sh symlinks to /bin/busybox, I tried to do this docker run -it container_name /bin/sh but it did not work. I changed default shell into bash by making a new image with below Dockerfile commands. $ echo $0 /bin/bash. Is there some way to tell RUN to use /bin/bash instead? Using bash with CMD ["command"]: When the CMD is specified as an array (i. 3 COPY . sh script is wrong, it's must be #!/bin/bash. Your shebang line in start. sh ENTRYPOINT ["/script. So you shouldn't need sudo. HEALTHCHECK --interval=2s CMD HealthCheckTest. This will /bin/sh is almost always available in containers, except when no shell can be found in that container. sh CMD env env. sh run start. Commented May 7, 2020 at 8:19 For these cases use: ' docker run -it --entrypoint /bin/bash ' Share. However, this command asks you to restart the shell, which we don't want to do inside docker. So the solution is to realize that the reason conda is asking you to restart Not sure if this is actually an issue related to Docker Desktop, but I’m out of ideas where to change following. sh"] BTW, as @user2915097 said, be careful that Alpine doesn't have Bash by default in case of your script using it in the shebang. As specified in docker run --help:. Conclusion. Then, in your Dockerfile, copy your bash file to your image, and use the ENTRYPOINT instruction for running the file when container is being created: COPY script. If for some reason your application needs sudo at runtime, my claim is that your application is This lets you execute commands within your BusyBox system since you’re now effectively sh-ing into your environment. /start. Simply add the option --user <user> to change to another user when you start the docker container. If you wish to update the running When you use the exec format for a command (e. RUN /Script. . sh). sh . In this tutorial, we have A: Docker run bash script is a command that allows you to run a Bash script inside a Docker container. sh whose contents are as below. This is a dirty hack, not a solution. sh / RUN chmod +x /script. /start. Could you please explain why? – Long. # Do this _before_ copying the entire application in # to avoid repeating it on rebuild RUN npm install # Includes wait-for-it. sh"] $ docker run -it openjdk:12-jdk-oraclelinux7 sh though the packaging tools there is yum Alternately, you could also build your own image with the openjdk toolset using the Dockerfiles from their GitHub repo as guidelines. 这也是一个命令，它将打开一个基本的 shell 提示，我们可以在容器中运行我们的命令。 To run a bash script in alpine based image, you need to do either one. html ; done Here is my naive Dockerfile that of course is not working: Actually, your Dockerfile and start. This is a popular Linux container image that uses Alpine Linux, a lightweight, minimal Linux distribution. My Dockerfile sets up a package (ros-indigo-desktop-full) which includes environment setup scripts in bash. docker run -d--name container-name alpine watch "date >> /var/log/date. sh, by running chmod +x start. But keep reading for more. Install bash $ RUN apk add --update bash Use #!/bin/sh in script instead of #!/bin/bash. Follow answered Jun 9, 2021 at 21:33. RUN bash -c 'nvm install 0. The docker exec command inherits the environment variables that are set at the time the container is created. sh entrypoint script work as is for me with Ctrl+C, provided you run the container with one of the following commands:. sh is the shell form of the RUN instruction, which will execute /bin/sh -c <command>. sh #!/bin/bash exit 0; Then build it with docker build --tag nginx-healthcheck-broken . sh file from current directory. g. /bin/sh: bash: not found. I'd like to incorporate these settings (like ROS_PATH) into the environment of the container. Above example will help you out. Dear all, I’m facing following while trying to start a container from an image I buid myself: Container command '/bin/sh' not found or does not exist. sh file but after running “echo Hello docker” it does CMD bash CMD ["/bin/sh", "-c", "bash"] There would not be an equivalent docker exec command. sh it will run: sudo chmod 755 upload. For example, you could either pre You must use . docker run -it <container_name> <image_name> or. /script. # Dockerfile. docker run --name tmp -it tmp; docker run --rm -it tmp; Documentation details. Option Default Description set environment variables in the current bash session. 12 && \ nvm alias default 0. That's why you have no way to enter the container again. mpiur vjfvt lsyjl wkjvgr vcvb ulkg xukzaxr zsnz hprmo mramv