How to run two docker containers from cron? - bash

I am trying to set up crontab to run two docker containers on system startup/reboot. The line I use to do this after entering the command crontab -e is:
#reboot sh folder_b/run_docker_containers.bash
The script run_docker_containers.bash has the following contents:
#!/bin/bash
# Run containers based on setup_image and main_image
sudo bash /home/user/folder_a/run_setup_docker_container.bash
sudo bash /home/user/folder_b/run_main_docker_container.bash
The scripts run_setup_docker_container.bash and run_main_docker_container.bash both have the following contents (where docker_image is setup_image and main_image, respectively):
#!/bin/bash
/snap/bin/docker run \
--rm \
--detach \
--privileged \
--net=host \
--device /dev/bus/usb \
docker_image:latest \
/bin/bash -c\
"
*SOME COMMANDS*
"
export containerId=$(/snap/bin/docker ps -l -q)
However, the containers are not run when the script is executed on reboot. I prove it finds the script folder_b/run_docker_containers.bash by adding the following code to it and seeing that the new file has been created after reboot.
touch proof_that_crontab_has_done_something.txt
It seems that crontab cannot find the scripts run_setup_docker_container.bash and run_main_docker_container.bash. Any ideas where I'm going wrong?

If you want to execute a shellscript with sudo rights I would recommend using the sudo crontab.
sudo crontab -e
Your personal cronjob should not be able to start a shell with sudo rights. Unless you do some weird modifications.
Use the absolute path
#reboot /...../folder_b/run_docker_containers.bash

Related

Docker run to execute script in mount without exiting container automatically?

I have a simple bash script 'test.sh' in the root of mounted folder :
#!/bin/bash
Rscript -e "source('/home/rstudio/mount-folder/src/controller.R')";
However, when i try to mount folder and start the container with docker run as follows:
docker run -d -p 8000:8787 -e ROOT=true -e DISABLE_AUTH=true --name container -v mount-folder/:/home/rstudio/ image_name /home/rstudio/test.sh
above run command starts the container but exits automatically.
I am looking for a docker run command that starts the container , mounts the folder and then executes the bash script which is in the mount-folder without exiting the container.
(** dont want to go with docker exec command as it is not suitable for my use case for other reasons)
Dockerfile:
FROM rocker/rstudio:4.0.2
//some RUN commands to install necessary r packages
EXPOSE 8787
CMD tail -f /dev/null
Other details :
Image that i am using is rstudio server from rocker and container runs on AWS ubuntu machine.
Edit :
have also tried adding CMD tail -f /dev/null at the end of dockerfile as suggested in http://bigdatums.net/2017/11/07/how-to-keep-docker-containers-running/ even then the container exits.
Docker containers shutdown automatically when run in detached mode. I think this article proposes a nice solution:
http://bigdatums.net/2017/11/07/how-to-keep-docker-containers-running/
You could add tail -f /dev/null as the last command in your bash script instead so that the script will never halt unless it is told to do so.
When you do docker run [options] image_name [cmd] the command you specify becomes the command for the container and replaces any the command specified in the dockerfile (that's why adding CMD tail -f /dev/null doesn't do anything). If you ran your container without the /home/rstudio/test.sh at the end, it should stay running.
The solution would be to update your script to add the tail command at the end.
#!/bin/bash
Rscript -e "source('/home/rstudio/mount-folder/src/controller.R')";
exec tail -f /dev/null
If you can't update that script, you could instead add it to the command being passed to the container, with something like:
docker run [options] image_name bash -c '/home/rstudio/test.sh && exec tail -f /dev/null'

Cant't build Jenkins latest within Docker

******** UPDATE *********
Bash script has no errors, checked with https://www.shellcheck.net/
Adding to the Dockerfilethe line
RUN tty | sed -e "s:/dev/::"
Outputs:
No tty
Next line on Dockerfile always fails:
ENTRYPOINT ["/usr/local/bin/jenkins.sh"]
I leave an image in order to clarify. In short, I think I need to attach a tty in some way to the batch script, but dunno how to do it.
Thanks
------------------- OLD CONTENT -------------------
I need to update a Jenkins image to 2.138.2. An excerpt of the original Dockerfile is as follows:
FROM openjdk:8-jdk
RUN apt-get update && apt-get install -y git curl && rm -rf /var/lib/apt/lists/*
# ...
# Use tini as subreaper in Docker container to adopt zombie processes
COPY tini_pub.gpg ${JENKINS_HOME}/tini_pub.gpg
RUN curl -fsSL https://github.com/krallin/tini/releases/download/${TINI_VERSION}/tini-static-$(dpkg --print-architecture) -o /sbin/tini \
&& curl -fsSL https://github.com/krallin/tini/releases/download/${TINI_VERSION}/tini-static-$(dpkg --print-architecture).asc -o /sbin/tini.asc \
&& gpg --import ${JENKINS_HOME}/tini_pub.gpg \
&& gpg --verify /sbin/tini.asc \
&& rm -rf /sbin/tini.asc /root/.gnupg \
# ...
ENTRYPOINT ["/sbin/tini", "--", "/usr/local/bin/jenkins.sh"]
Using this Dockerfile FAILS due to gpg --import statement now needs to be fixed using --no-tty option. So that line remains as follows:
&& gpg --no-tty --import ${JENKINS_HOME}/tini_pub.gpg \
That's not fine since the execution of jenkins.sh now fails in several ways. The code of the script starts as follows:
#! /bin/bash -e
: "${JENKINS_WAR:="/usr/share/jenkins/jenkins.sh
This script is called from the Dockerfile in this line:
ENTRYPOINT ["/sbin/tini", "--", "/usr/local/bin/jenkins.sh"]
But now fails with several errors and seems to be impossible to process the file, nor removing the shebang line, nor removing the '-' or the '-e' option. The rest of the file is not processed fine if we change bash to other shell (not odd) nor removing the -e option (if I do that, the entrypoint does not find the jenkins.sh script).
Sumarizing, I've needed to remove a tty from gpg but doing that, I've lost access to bash scripting.
I've checked about the applied workaround, the workaround is described here ( (if I'm right, case is number 8, gpg might write to the tty at some point):
https://lists.gnupg.org/pipermail/gnupg-users/2017-April/058162.html
Is there any way to attach a tty to the entrypointor having any settings in the script in order to allow this work fine?
Thanks.
Finally runned on a Linux VM and no problems. Running it on Windows is the problem.

Source script on interactive shell inside Docker container

I want to open a interactive shell which sources a script to use the bitbake environment on a repository that I bind mount:
docker run --rm -it \
--mount type=bind,source=$(MY_PATH),destination=/mnt/bb_repoistory \
my_image /bin/bash -c "cd /mnt/bb_repoistory/oe-core && source build/conf/set_bb_env.sh"
The problem is that the -it argument does not seem to have any effect, since the shell exits right after executing cd /mnt/bb_repoistory/oe-core && source build/conf/set_bb_env.sh
I also tried this:
docker run --rm -it \
--mount type=bind,source=$(MY_PATH),destination=/mnt/bb_repoistory \
my_image /bin/bash -c "cd /mnt/bb_repoistory/oe-core && source build/conf/set_bb_env.sh && bash"
Which spawns an interactive shell, but none of the macros defined in set_bb_env.sh
Would there be a way to provide a tty with the script properly sourcered ?
The -it flag is conflicting with the command to run in that you're telling docker to create the pseudo-terminal (ptty), and then running a command in that terminal (bash -c ...). When that command finishes, then the run is done.
What some people have done to work around this is to only have export variables in their sourced environment, and the last command would be exec bash. But if you need aliases or other items that aren't inherited like that, then your options are a bit more limited.
Instead of running the source in a parent shell, you could run it in the target shell. If you modified your .bash_profile to include the following line:
[ -n "$DOCKER_LOAD_EXTRA" -a -r "$DOCKER_LOAD_EXTRA" ] && source "$DOCKER_LOAD_EXTRA”
and then had your command be:
... /bin/bash -c "cd /mnt/bb_repository/oe-core && DOCKER_LOAD_EXTRA=build/conf/set_bb_env.sh exec bash"
that may work. This tells your .bash_profile to load this file when the env variable is already set, but not otherwise. (There can also be the -e flag on the docker command line, but I think that sets it globally for the entire container, which is probably not what you want.)

Run a Docker Container from a Desktop File Without Terminal GUI?

I have a couple of Docker images I've built for this and that;one for scanner program, another for a browser etc. Once I had them working, I created .desktop files that execute a bash run scripts I've created to run a container with them.
My question is: is there a way to run the .desktop file without the terminal GUI showing up? I've tried a couple of approaches with no success.
For instance, I've tried:
[Desktop Entry]
Name=gscan2pdf
Icon=gscan2pdf.png
Exec=gnome-terminal -e
"/home/hildy/Documents/repos/docker/gscan2pdf/run_gscan.sh"
Type=Application
Terminal=false
As well as:
[Desktop Entry]
Name=gscan2pdf
Icon=gscan2pdf.png
Exec="/home/hildy/Documents/repos/docker/gscan2pdf/run_gscan.sh"
Type=Application
Terminal=true
Both of these execute the scripts just fine of course, I'd just like it better if the application launched without a terminal GUI launching first.
Host System:
CentOS 7 - Gnome 3 Desktop
One example of a run script:
#!/bin/bash
HOST_UID=$(id -u)
HOST_GID=$(id -g)
XSOCK=/tmp/.X11-unix &&
XAUTH=/tmp/.docker.xauth &&
touch $XAUTH &&
xauth nlist :0 | sed -e 's/^..../ffff/' | xauth -f $XAUTH nmerge - &&
#These are only run the first time a container is run from the image
#docker run -e NEW_USER="${USER}" -e NEW_UID="${HOST_UID}" -e
#NEW_GID="${HOST_GID}" hildy/gscan2pdf:v1
#LAST_CONTAINER=$(docker ps -lq) &&
#docker commit "${LAST_CONTAINER}" hildy/gscan2pdf:v1
docker run \
-ti \
--user $USER \
--privileged \
-v /dev/bus/usb:/dev/bus/usb \
-v $XAUTH:$XAUTH -v $XSOCK:$XSOCK -v /home/$USER:/home/$USER \
-e XAUTHORITY=$XAUTH -e DISPLAY \
--entrypoint "" hildy/gscan2pdf:v1 gscan2pdf &>/dev/null
I have found an answer to my question. The issue was that the command to run the container contained the -i option for an interactive terminal. #sneep was correct in the comments to the question when he said "It should work with Terminal=false." His technique to add a line to the script to create a log file is also a great technique, which I will certainly use in the future and it helped me to diagnose the issue.
I can also confirm that replacing -it with -d for detached mode, as suggested by #Oleg Skylar, works.
Amended Docker command for the run script:
docker run \
-t \
--user $USER \
--privileged \
-v /dev/bus/usb:/dev/bus/usb \
-v $XAUTH:$XAUTH -v $XSOCK:$XSOCK -v /home/$USER:/home/$USER \
-e XAUTHORITY=$XAUTH -e DISPLAY \
--entrypoint "" hildy/gscan2pdf:v1 gscan2pdf &>/dev/null
Amended .desktop file:
[Desktop Entry]
Name=gscan2pdf
Icon=gscan2pdf.png
Exec=/home/hildy/Documents/repos/docker/gscan2pdf/run_gscan.sh
Type=Application
Terminal=false
StartupNotify=true

How can I set Bash aliases for docker containers in Dockerfile?

I am new to Docker. I found that we can set environment variables using the ENV instruction in the Dockerfile. But how does one set Bash aliases for long commands in Dockerfile?
Basically like you always do, by adding it to the user's .bashrc file:
FROM foo
RUN echo 'alias hi="echo hello"' >> ~/.bashrc
As usual this will only work for interactive shells:
docker build -t test .
docker run -it --rm --entrypoint /bin/bash test hi
/bin/bash: hi: No such file or directory
docker run -it --rm test bash
$ hi
hello
For non-interactive shells you should create a small script and put it in your path, i.e.:
RUN echo -e '#!/bin/bash\necho hello' > /usr/bin/hi && \
chmod +x /usr/bin/hi
If your alias uses parameters (ie. hi Jim -> hello Jim), just add "$#":
RUN echo -e '#!/bin/bash\necho hello "$#"' > /usr/bin/hi && \
chmod +x /usr/bin/hi
To create an alias of an existing command, might also use ln -s:
ln -s $(which <existing_command>) /usr/bin/<my_command>
If you want to use aliases just in Dockerfile, but not inside a container then the shortest way is the ENV declaration:
ENV update='apt-get update -qq'
ENV install='apt-get install -qq'
RUN $update && $install apt-utils \
curl \
gnupg \
python3.6
And for use in a container the way like already described:
RUN printf '#!/bin/bash \n $(which apt-get) install -qq $#' > /usr/bin/install
RUN chmod +x /usr/bin/install
Most of the time I use aliases just in the building stage and do not go inside containers, so the first example is quicker, clearer and simpler for every day use.
I just added this to my app.dockerfile file:
# Set up aliases
ADD ./bashrc_alias.sh /usr/sbin/bashrc_alias.sh
ADD ./initbash_profile.sh /usr/sbin/initbash_profile
RUN chmod +x /usr/sbin/initbash_profile
RUN /bin/bash -C "/usr/sbin/initbash_profile"
And inside the initbash_profile.sh file which just appends my custom aliases and no need to source the .bashrc file:
# Add the Bash aliases
cat /usr/sbin/bashrc_alias.sh >> ~/.bashrc
It worked a treat!
Another option is to just use the "docker exec -it <container-name> command" from outside the container and just use your own .bashrc or the .bash_profile file (what ever you prefer).
E.g.,
docker exec -it docker_app_1 bash
I think the easiest way would be to mount a file into your container containing your aliases, and then specify where Bash should find it:
docker run \
-it \
--rm \
-v ~/.bash_aliases:/tmp/.bash_aliases \
[image] \
/bin/bash --init-file /tmp/.bash_aliases
Sample usage:
echo 'alias what="echo it works"' > my_aliases
docker run -it --rm -v ~/my_aliases:/tmp/my_aliases ubuntu:18.04 /bin/bash --init-file /tmp/my_aliases
alias
Output:
alias what='echo it works'
what
Output:
it works
You can use ENTRYPOINT, but it will not work for aliases, in your Dockerfile:
ADD dev/entrypoint.sh /opt/entrypoint.sh
ENTRYPOINT ["/opt/entrypoint.sh"]
Your entrypoint.sh file:
#!/bin/bash
set -e
function dev_run()
{
}
export -f dev_run
exec "$#"
Here is a Bash function to have your aliases in every container you use interactively.
ducker_it() {
docker cp ~/bin/alias.sh "$1":/tmp
docker exec -it "$1" /bin/bash -c "[[ ! -f /tmp/alias.sh.done ]] \
&& [[ -w /root/.bashrc ]] \
&& cat /tmp/alias.sh >> /root/.bashrc \
&& touch /tmp/alias.sh.done"
docker exec -it "$1" /bin/bash
}
Required step before:
grep ^alias ~/.zshrc > ~/bin/alias.sh
Used some of the previous solutions, but the aliases are not recognised still.
I'm trying to set aliases and use them both within later Dockerfile steps and in the container at runtime.
RUN echo "alias model-downloader='python3 ${MODEL_DL_PATH}/downloader.py'" >> ~/.bash_aliases && \
echo "alias model-converter='python3 ${MODEL_DL_PATH}/converter.py'" >> ~/.bash_aliases && \
source ~/.bash_aliases
# Download the model
RUN model-downloader --name $MODEL_NAME -o $MODEL_DIR --precisions $MODEL_PRECISION;
The solution for me was to use ENV variables that held folder paths and then add the exact executable. I could have use ARG too, but for more of my scenarios I needed the aliases in both the build stage and later in the runtime.
I used the ENV variables in conjunction with a Bash script that runs once dependencies have ponged and sets the Bash source, sets some more env variables, and allows for further commands to pipe through.
#ErikDannenberg's answer did the trick, but in my case, some adjustments were needed.
It didn't work with aliases cause apparently there's an issue with interactive shells.
I reached for his second solution, but it still didn't really work. I checked existing shell scripts in my project and noticed the head comment (first line = #!/usr/bin/env sh) differs a bit from #!/usr/bin/bash. After changing it accordingly it started working for my t and tc "aliases", but I had to use the addendum to his second solution for getting tf to work.
Here's the complete Dockerfile
FROM php:8.1.1-fpm-alpine AS build
RUN apk update && apk add git
RUN curl -sS https://getcomposer.org/installer | php && mv composer.phar /usr/local/bin/composer
RUN apk add --no-cache $PHPIZE_DEPS \
&& pecl install xdebug \
&& docker-php-ext-enable xdebug \
&& touch /usr/local/etc/php/conf.d/99-xdebug.ini \
&& echo "xdebug.mode=coverage" >> /usr/local/etc/php/conf.d/99-xdebug.ini \
&& echo -e '#!/usr/bin/env sh\nphp artisan test' > /usr/bin/t \
&& chmod +x /usr/bin/t \
&& echo -e '#!/usr/bin/env sh\nphp artisan test --coverage' > /usr/bin/tc \
&& chmod +x /usr/bin/tc \
&& echo -e '#!/usr/bin/env sh\nphp artisan test --filter "$#"' > /usr/bin/tf \
&& chmod +x /usr/bin/tf
WORKDIR /var/www

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