I know technically host networking isn't supported MacOS (see https://docs.docker.com/network/host/)
The host networking driver only works on Linux hosts, and is not
supported on Docker Desktop for Mac, Docker Desktop for Windows, or
Docker EE for Windows Server.
However it does actually seem to work. E.g. this works just fine:
docker run \
--name local-mysql \
-e MYSQL_ROOT_PASSWORD=foo \
-e MYSQL_DATABASE=baz \
--network="host" \
-d mysql:latest
However when I try to conditionally specify the host networking with a bash variable, it doesn't work, and I can't make sense of it. Consider the following test.sh:
#!/bin/bash
echo "Test 1"
docker rm -f local-mysql
docker run \
--name local-mysql \
-e MYSQL_ROOT_PASSWORD=foo \
-e MYSQL_USER=master \
-e MYSQL_PASSWORD=bar \
-e MYSQL_DATABASE=baz \
--network="host" \
-d mysql:latest
docker ps
sleep 5
echo "Test 2"
export NETWORKING='--network="host"'
docker rm -f local-mysql
docker run \
--name local-mysql \
-e MYSQL_ROOT_PASSWORD=foo \
-e MYSQL_USER=master \
-e MYSQL_PASSWORD=bar \
-e MYSQL_DATABASE=baz \
${NETWORKING} \
-d mysql:latest
docker ps
This yields:
% ./test.sh
Test 1
local-mysql
6bbd68f0564943b8fb66ed37f1e639b54719bdb3b88b4e13aeef0a11cae4090b
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
6bbd68f05649 mysql:latest "docker-entrypoint.s…" Less than a second ago Up Less than a second local-mysql
Test 2
local-mysql
e286028ef9a1a27f4226beb60e766cc163c289239ba506f63a71a35adbc73ef3
docker: Error response from daemon: network "host" not found.
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
I.e. when I hard code --network=host into the docker command, the container starts fine. But the exact same parameter in an environment variable fails to start with network "host" not found.
I'm honestly not sure if this is a failure of bash or docker, but I can't actually figure out what's going wrong.
-- EDIT --
Changing
export NETWORKING='--network="host"'
to
export NETWORKING='--network=host'
works. And for my purposes right now that's enough. But just to be thorough... Why? The working example has quotes in the value (--network="host"), so why does the shell expansion break the non-working example? What if I wanted something like --network="my host"?
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
I'm trying to create a shell script to run a docker container and am struggling. My script is like this:
#!/bin/bash
if [ "$1" == "" ]; then
echo "Usage > run.sh IMAGE NAME"
echo
echo "i.e. ./build.sh cd2:0.0.49"
exit
fi
echo $1
docker run -it --rm \
-e NODE_PATH='./src'\
-e NODE_HOST='0.0.0.0'\
-e NODE_ENV='production'\
-e DOCKER=true\
-e PORT='8080'\
-e STAGING=true\
-e SENDGRID_API_KEY='<redacted>'\
-p 8080:8080 $1
When I run: bash run.sh cd2:0.0.50
I get: docker: invalid reference format: repository name must be lowercase.
Even if I do bash run.sh cd:0.0.50 it still fails (echo $1 results in cd2:0.0.50).
If I run docker run -it --rm -p 8080:8080 cd2:0.0.50 from the command line it works...
Can anyone help?
docker run \
-e NODE_PATH='./src' \
-e NODE_HOST='0.0.0.0' \
-e NODE_ENV='production' \
-e DOCKER=true \
-e PORT='8080' \
-e STAGING=true \
-e SENDGRID_API_KEY='<redacted>' \
-p 8080:8080 --rm -it $1
The image name should be immediately after the -it parameter and so re arrange your run command.
Is it possible to generate a Dockerfile from an image? I want to know for two reasons:
I can download images from the repository but would like to see the recipe that generated them.
I like the idea of saving snapshots, but once I am done it would be nice to have a structured format to review what was done.
How to generate or reverse a Dockerfile from an image?
You can. Mostly.
Notes: It does not generate a Dockerfile that you can use directly with docker build; the output is just for your reference.
alias dfimage="docker run -v /var/run/docker.sock:/var/run/docker.sock --rm alpine/dfimage"
dfimage -sV=1.36 nginx:latest
It will pull the target docker image automatically and export Dockerfile. Parameter -sV=1.36 is not always required.
Reference: https://hub.docker.com/r/alpine/dfimage
Now hub.docker.com shows the image layers with detail commands directly, if you choose a particular tag.
Bonus
If you want to know which files are changed in each layer
alias dive="docker run -ti --rm -v /var/run/docker.sock:/var/run/docker.sock wagoodman/dive"
dive nginx:latest
On the left, you see each layer's command, on the right (jump with tab), the yellow line is the folder that some files are changed in that layer
(Use SPACE to collapse dir)
Old answer
below is the old answer, it doesn't work any more.
$ docker pull centurylink/dockerfile-from-image
$ alias dfimage="docker run -v /var/run/docker.sock:/var/run/docker.sock --rm centurylink/dockerfile-from-image"
$ dfimage --help
Usage: dockerfile-from-image.rb [options] <image_id>
-f, --full-tree Generate Dockerfile for all parent layers
-h, --help Show this message
To understand how a docker image was built, use the
docker history --no-trunc command.
You can build a docker file from an image, but it will not contain everything you would want to fully understand how the image was generated. Reasonably what you can extract is the MAINTAINER, ENV, EXPOSE, VOLUME, WORKDIR, ENTRYPOINT, CMD, and ONBUILD parts of the dockerfile.
The following script should work for you:
#!/bin/bash
docker history --no-trunc "$1" | \
sed -n -e 's,.*/bin/sh -c #(nop) \(MAINTAINER .*[^ ]\) *0 B,\1,p' | \
head -1
docker inspect --format='{{range $e := .Config.Env}}
ENV {{$e}}
{{end}}{{range $e,$v := .Config.ExposedPorts}}
EXPOSE {{$e}}
{{end}}{{range $e,$v := .Config.Volumes}}
VOLUME {{$e}}
{{end}}{{with .Config.User}}USER {{.}}{{end}}
{{with .Config.WorkingDir}}WORKDIR {{.}}{{end}}
{{with .Config.Entrypoint}}ENTRYPOINT {{json .}}{{end}}
{{with .Config.Cmd}}CMD {{json .}}{{end}}
{{with .Config.OnBuild}}ONBUILD {{json .}}{{end}}' "$1"
I use this as part of a script to rebuild running containers as images:
https://github.com/docbill/docker-scripts/blob/master/docker-rebase
The Dockerfile is mainly useful if you want to be able to repackage an image.
The thing to keep in mind, is a docker image can actually just be the tar backup of a real or virtual machine. I have made several docker images this way. Even the build history shows me importing a huge tar file as the first step in creating the image...
I somehow absolutely missed the actual command in the accepted answer, so here it is again, bit more visible in its own paragraph, to see how many people are like me
$ docker history --no-trunc <IMAGE_ID>
A bash solution :
docker history --no-trunc $argv | tac | tr -s ' ' | cut -d " " -f 5- | sed 's,^/bin/sh -c #(nop) ,,g' | sed 's,^/bin/sh -c,RUN,g' | sed 's, && ,\n & ,g' | sed 's,\s*[0-9]*[\.]*[0-9]*\s*[kMG]*B\s*$,,g' | head -n -1
Step by step explanations:
tac : reverse the file
tr -s ' ' trim multiple whitespaces into 1
cut -d " " -f 5- remove the first fields (until X months/years ago)
sed 's,^/bin/sh -c #(nop) ,,g' remove /bin/sh calls for ENV,LABEL...
sed 's,^/bin/sh -c,RUN,g' remove /bin/sh calls for RUN
sed 's, && ,\n & ,g' pretty print multi command lines following Docker best practices
sed 's,\s*[0-9]*[\.]*[0-9]*\s*[kMG]*B\s*$,,g' remove layer size information
head -n -1 remove last line ("SIZE COMMENT" in this case)
Example:
~ dih ubuntu:18.04
ADD file:28c0771e44ff530dba3f237024acc38e8ec9293d60f0e44c8c78536c12f13a0b in /
RUN set -xe
&& echo '#!/bin/sh' > /usr/sbin/policy-rc.d
&& echo 'exit 101' >> /usr/sbin/policy-rc.d
&& chmod +x /usr/sbin/policy-rc.d
&& dpkg-divert --local --rename --add /sbin/initctl
&& cp -a /usr/sbin/policy-rc.d /sbin/initctl
&& sed -i 's/^exit.*/exit 0/' /sbin/initctl
&& echo 'force-unsafe-io' > /etc/dpkg/dpkg.cfg.d/docker-apt-speedup
&& echo 'DPkg::Post-Invoke { "rm -f /var/cache/apt/archives/*.deb /var/cache/apt/archives/partial/*.deb /var/cache/apt/*.bin || true"; };' > /etc/apt/apt.conf.d/docker-clean
&& echo 'APT::Update::Post-Invoke { "rm -f /var/cache/apt/archives/*.deb /var/cache/apt/archives/partial/*.deb /var/cache/apt/*.bin || true"; };' >> /etc/apt/apt.conf.d/docker-clean
&& echo 'Dir::Cache::pkgcache ""; Dir::Cache::srcpkgcache "";' >> /etc/apt/apt.conf.d/docker-clean
&& echo 'Acquire::Languages "none";' > /etc/apt/apt.conf.d/docker-no-languages
&& echo 'Acquire::GzipIndexes "true"; Acquire::CompressionTypes::Order:: "gz";' > /etc/apt/apt.conf.d/docker-gzip-indexes
&& echo 'Apt::AutoRemove::SuggestsImportant "false";' > /etc/apt/apt.conf.d/docker-autoremove-suggests
RUN rm -rf /var/lib/apt/lists/*
RUN sed -i 's/^#\s*\(deb.*universe\)$/\1/g' /etc/apt/sources.list
RUN mkdir -p /run/systemd
&& echo 'docker' > /run/systemd/container
CMD ["/bin/bash"]
Update Dec 2018 to BMW's answer
chenzj/dfimage - as described on hub.docker.com regenerates Dockerfile from other images. So you can use it as follows:
docker pull chenzj/dfimage
alias dfimage="docker run -v /var/run/docker.sock:/var/run/docker.sock --rm chenzj/dfimage"
dfimage IMAGE_ID > Dockerfile
This is derived from #fallino's answer, with some adjustments and simplifications by using the output format option for docker history. Since macOS and Gnu/Linux have different command-line utilities, a different version is necessary for Mac. If you only need one or the other, you can just use those lines.
#!/bin/bash
case "$OSTYPE" in
linux*)
docker history --no-trunc --format "{{.CreatedBy}}" $1 | # extract information from layers
tac | # reverse the file
sed 's,^\(|3.*\)\?/bin/\(ba\)\?sh -c,RUN,' | # change /bin/(ba)?sh calls to RUN
sed 's,^RUN #(nop) *,,' | # remove RUN #(nop) calls for ENV,LABEL...
sed 's, *&& *, \\\n \&\& ,g' # pretty print multi command lines following Docker best practices
;;
darwin*)
docker history --no-trunc --format "{{.CreatedBy}}" $1 | # extract information from layers
tail -r | # reverse the file
sed -E 's,^(\|3.*)?/bin/(ba)?sh -c,RUN,' | # change /bin/(ba)?sh calls to RUN
sed 's,^RUN #(nop) *,,' | # remove RUN #(nop) calls for ENV,LABEL...
sed $'s, *&& *, \\\ \\\n \&\& ,g' # pretty print multi command lines following Docker best practices
;;
*)
echo "unknown OSTYPE: $OSTYPE"
;;
esac
It is not possible at this point (unless the author of the image explicitly included the Dockerfile).
However, it is definitely something useful! There are two things that will help to obtain this feature.
Trusted builds (detailed in this docker-dev discussion
More detailed metadata in the successive images produced by the build process. In the long run, the metadata should indicate which build command produced the image, which means that it will be possible to reconstruct the Dockerfile from a sequence of images.
If you are interested in an image that is in the Docker hub registry and wanted to take a look at Dockerfile?.
Example:
If you want to see the Dockerfile of image "jupyter/datascience-notebook" type the word "Dockerfile" in the address bar of your browser as shown below.
https://hub.docker.com/r/jupyter/datascience-notebook/
https://hub.docker.com/r/jupyter/datascience-notebook/Dockerfile
Note:
Not all the images have Dockerfile, for example, https://hub.docker.com/r/redislabs/redisinsight/Dockerfile
Sometimes this way is much faster than searching for Dockerfile in Github.
docker pull chenzj/dfimage
alias dfimage="docker run -v /var/run/docker.sock:/var/run/docker.sock --rm chenzj/dfimage"
dfimage image_id
Below is the output of the dfimage command:
$ dfimage 0f1947a021ce
FROM node:8
WORKDIR /usr/src/app
COPY file:e76d2e84545dedbe901b7b7b0c8d2c9733baa07cc821054efec48f623e29218c in ./
RUN /bin/sh -c npm install
COPY dir:a89a4894689a38cbf3895fdc0870878272bb9e09268149a87a6974a274b2184a in .
EXPOSE 8080
CMD ["npm" "start"]
it is possible in just two step. First pull the image then run docker history command. also, shown in SS.
docker pull kalilinux/kali-rolling
docker history --format "{{.CreatedBy}}" kalilinux/kali-rolling --no-trunc
What is image2df
image2df is tool for Generate Dockerfile by an image.
This tool is very useful when you only have docker image and need to generate a Dockerfile whit it.
How does it work
Reverse parsing by history information of an image.
How to use this image
# Command alias
echo "alias image2df='docker run -v /var/run/docker.sock:/var/run/docker.sock --rm cucker/image2df'" >> ~/.bashrc
. ~/.bashrc
# Excute command
image2df <IMAGE>
See help
docker run --rm cucker/image2df --help
For example
$ echo "alias image2df='docker run -v /var/run/docker.sock:/var/run/docker.sock --rm cucker/image2df'" >> ~/.bashrc
$ . ~/.bashrc
$ docker pull mysql
$ image2df mysql
========== Dockerfile ==========
FROM mysql:latest
RUN groupadd -r mysql && useradd -r -g mysql mysql
RUN apt-get update && apt-get install -y --no-install-recommends gnupg dirmngr && rm -rf /var/lib/apt/lists/*
ENV GOSU_VERSION=1.12
RUN set -eux; \
savedAptMark="$(apt-mark showmanual)"; \
apt-get update; \
apt-get install -y --no-install-recommends ca-certificates wget; \
rm -rf /var/lib/apt/lists/*; \
dpkgArch="$(dpkg --print-architecture | awk -F- '{ print $NF }')"; \
wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch"; \
wget -O /usr/local/bin/gosu.asc "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch.asc"; \
export GNUPGHOME="$(mktemp -d)"; \
gpg --batch --keyserver hkps://keys.openpgp.org --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
gpgconf --kill all; \
rm -rf "$GNUPGHOME" /usr/local/bin/gosu.asc; \
apt-mark auto '.*' > /dev/null; \
[ -z "$savedAptMark" ] || apt-mark manual $savedAptMark > /dev/null; \
apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false; \
chmod +x /usr/local/bin/gosu; \
gosu --version; \
gosu nobody true
RUN mkdir /docker-entrypoint-initdb.d
RUN apt-get update && apt-get install -y --no-install-recommends \
pwgen \
openssl \
perl \
xz-utils \
&& rm -rf /var/lib/apt/lists/*
RUN set -ex; \
key='A4A9406876FCBD3C456770C88C718D3B5072E1F5'; \
export GNUPGHOME="$(mktemp -d)"; \
gpg --batch --keyserver ha.pool.sks-keyservers.net --recv-keys "$key"; \
gpg --batch --export "$key" > /etc/apt/trusted.gpg.d/mysql.gpg; \
gpgconf --kill all; \
rm -rf "$GNUPGHOME"; \
apt-key list > /dev/null
ENV MYSQL_MAJOR=8.0
ENV MYSQL_VERSION=8.0.24-1debian10
RUN echo 'deb http://repo.mysql.com/apt/debian/ buster mysql-8.0' > /etc/apt/sources.list.d/mysql.list
RUN { \
echo mysql-community-server mysql-community-server/data-dir select ''; \
echo mysql-community-server mysql-community-server/root-pass password ''; \
echo mysql-community-server mysql-community-server/re-root-pass password ''; \
echo mysql-community-server mysql-community-server/remove-test-db select false; \
} | debconf-set-selections \
&& apt-get update \
&& apt-get install -y \
mysql-community-client="${MYSQL_VERSION}" \
mysql-community-server-core="${MYSQL_VERSION}" \
&& rm -rf /var/lib/apt/lists/* \
&& rm -rf /var/lib/mysql && mkdir -p /var/lib/mysql /var/run/mysqld \
&& chown -R mysql:mysql /var/lib/mysql /var/run/mysqld \
&& chmod 1777 /var/run/mysqld /var/lib/mysql
VOLUME [/var/lib/mysql]
COPY dir:2e040acc386ebd23b8571951a51e6cb93647df091bc26159b8c757ef82b3fcda in /etc/mysql/
COPY file:345a22fe55d3e6783a17075612415413487e7dba27fbf1000a67c7870364b739 in /usr/local/bin/
RUN ln -s usr/local/bin/docker-entrypoint.sh /entrypoint.sh # backwards compat
ENTRYPOINT ["docker-entrypoint.sh"]
EXPOSE 3306 33060
CMD ["mysqld"]
reference