View installed packages in a docker container [duplicate] - docker

This question already has an answer here:
Is there any way by which we can list out all the dependencies or libraries installed in running docker container?
(1 answer)
Closed 2 years ago.
There are containers raised in Docker. Containers run applications such as nginx, apache, etc.
How can I list the installed versions of those applications in each container?

Use the command docker container inspect <container-id>
$ docker container inspect --format '{{.Config.Env}}' cfa
[PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin NGINX_VERSION=1.17.7 NJS_VERSION=0.3.7 PKG_RELEASE=1~buster]

What do you want? Check all versions? List all packages?
Type this inside container shell to check nginx/apache version:
$ nginx -v #=> Nginx
$ httpd -v #=> Apache
To connect to container bash (for example alpine):
$ docker container run -it alpine /bin/sh

Related

Docker linux versions [duplicate]

This question already has answers here:
$(uname -a) returning the same in docker host or any docker container
(2 answers)
Closed 1 year ago.
I am learning docker basics. I created a simple image
FROM alpine
RUN apk add --update redis
CMD ["redis-server"]
I started the container and logged in using
docker exec -it c57389dc94f5 sh
From the shell prompt, if I execute
more /etc/alpine-release
I get 3.14.2.
If I execute
more /proc/version
I get
Linux version 5.4.0-84-generic (buildd#lgw01-amd64-050) (gcc version 9.3.0 (Ubuntu 9.3.0-17ubuntu1~20.04)) #94-Ubuntu SMP Thu Aug 26 20:27:37 UTC 2021
Why am I getting Ubuntu when the image uses Alpine?
/cat/proc give you the version of the OS which hosts the docker container, and not the docker image version. Remember that docker is not a virtual machine, but a bunch of isolated processes, named container, running on top of the hosting OS (and so, by its own kernel).
I guess that you are using docker on Ubuntu. Is it right?
Please refer to official docker containers architecture.

Docker Bind Mounts in WSL do not show files

Im trying to use the docker client from inside WSL, connecting to the docker engine on Windows. Ive exposed the docker engine on Windows on port 2375, and after setting the DOCKER_HOST environment variable in WSL, I can verify this works by running docker ps.
The problem comes when i attempt to mount directories into docker containers from WSL. For example:
I create a directory and file inside my home folder on WSL (mkdir ~/dockertest && touch ~/dockertest/example.txt)
ls ~/dockertest shows my file has been created
I now start a docker container, mounting my docker test folder (docker run -it --rm -v ~/dockertest:/data alpine ls /data)
I would expect to see 'example.txt' in the docker container, but this does not seem to be happening.
Any ideas what I might be missing?
There are great instructions for Docker setup in WSL at https://nickjanetakis.com/blog/setting-up-docker-for-windows-and-wsl-to-work-flawlessly#ensure-volume-mounts-work - solved most of my problems. The biggest trick for me was with bind-mounted directories; you have to use a path in WSL that the Docker daemon will be able to translate, for example /c/Users/rfay/myproject.
I don't think you need to change the mound point as the link suggests. Rather if you use pwd and sed in combination you should get the effect you need.
docker run -it -v $(pwd | sed 's/^\/mnt//'):/var/folder -w "/var/folder" alpine
pwd returns the working folder in the format '/mnt/c/code/folder'. Pipe this to sed and replace '/mnt' with empty string will leave you with a path such as '/c/code/folder' which is correct for docker for windows.
Anyone stumbling here over this issue follow this: Docker Desktop WSL2 Backend and make sure you are running the version 2 of the WSL in PowerShell:
> wsl -l -v
NAME STATE VERSION
* docker-desktop Running 2
Ubuntu Running 2
docker-desktop-data Running 2
If your Ubuntu VERSION doesn't say 2, you need to update it according to the guide above.
After that, you will be able to mount your Linux directory to the Docker Container directly like:
docker run -v ~/my-project:/sources <my-image>
Specific to WSL 1
Ran into the same issue. One thing to remember is that docker run command does not execute a container then and there on a command shell. It sends the run arguments to a docker daemon that does not interpret WSL path correctly. Hence, you need to pass Windows formatted path in quotes and with back slashes escaped
Your Windows path is
\\wsl$\Ubuntu\home\username\dockertest
Docker command after escaping will probably be like
docker run -it --rm -v "\\\\wsl\$\\Ubuntu\\home\\username\\dockertest":/data alpine ls /data
try
docker -v /:{path} exe
Hope to help you.

Start an existing docker ubuntu container [duplicate]

This question already has answers here:
How to continue a Docker container which has exited
(14 answers)
Closed 6 years ago.
A related question & answer on How to start a docker container (ubuntu image) suggest using docker run -it ubuntu to start a ubuntu container and connect to it. However the run command creates and starts a new ubuntu container.
How do we start an existing docker container (ubuntu image) given it's CONTAINER_ID without creating a new container?
Example:
docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
9f297d02f419 ubuntu "/bin/bash" 3 seconds ago Exited (0) 1 seconds ago cranky_wilson
How do we start 9f297d02f419 ?
you can start the stopped container using docker start command -
eg:
docker start 9f297d02f419
If you just use run on the Ubuntu image it will start a container that's running no command, which will immediately stop. You can docker start it but it will stop again. You can see it with docker ps -a.
The accepted answer in that question is very old and not very good. If you run that command on the current Docker version you get an error No command specified!
What you need to do is tell that container to run a command:
docker run ubuntu date
Will run a container from the image, run the date command, then exit. If you want to keep it running indefinitely, try something like:
docker run -d ubuntu tail -f /dev/null
You should see that the container is now running. The -d makes it run in the background, otherwise it will occupy your shell. And the final piece of the puzzle: since we have a container now that's configured to run a command, you can use docker ps to find its ID, and you can docker stop and docker start it at will.

Bind to docker socket on Windows

On *nix systems, it is possible to bind-mount the docker socket from the host machine to the VM by doing something like this:
docker run -v /var/run/docker.sock:/var/run/docker.sock ...
Is there an equivalent way to do this when running docker on a windows host?
I tried various combinations like:
docker run -v tcp://127.0.0.1:2376:/var/run/docker.sock ...
docker run -v "tcp://127.0.0.1:2376":/var/run/docker.sock ...
docker run -v localhost:2376:/var/run/docker.sock ...
none of these have worked.
For Docker for Windows following seems to be working:
-v //var/run/docker.sock:/var/run/docker.sock
As the Docker documentation states:
If you are using Docker Machine on Mac or Windows, your Engine daemon
has only limited access to your OS X or Windows filesystem. Docker
Machine tries to auto-share your /Users (OS X) or C:\Users (Windows)
directory. So, you can mount files or directories on OS X using:
docker run -v /Users/<path>:/<container path> ...
On Windows, mount directories using:
docker run -v /c/Users/<path>:/<container path> ...
All other paths come from your virtual machine’s filesystem, so if you
want to make some other host folder available for sharing, you need to
do additional work. In the case of VirtualBox you need to make the
host folder available as a shared folder in VirtualBox. Then, you can
mount it using the Docker -v flag.
With all that being said, you can still use the:
docker run -v /var/run/docker.sock:/var/run/docker.sock ...
The first /var/run/docker.sock refers to the same path in your boot2docker virtual machine.
For example, when I run my own Jenkins image using the following command in a Windows machine:
$ docker run -dP -v /var/run/docker.sock:/var/run/docker.sock alidehghanig/jenkins
I can still talk to the Docker Daemon in the host machine using the typical docker commands. For example, when I run docker ps in the Jenkins container, I can see running containers in the host machine:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
65311731f446 jen... "/bi.." 10... Up 10.. 0.0.0.0:.. jenkins
Just to top it off on the answers provided earlier
When using docker-compose, one must set the COMPOSE_CONVERT_WINDOWS_PATHS=1 by either:
1) create a .env file at the same location as the project's docker-compose.yml file
2) in the CLI set COMPOSE_CONVERT_WINDOWS_PATHS=1
before running the docker-compose up command.
source
This never worked for me on Windows 10 even if it is a linux container:
-v /var/run/docker.sock:/var/run/docker.sock
But this did:
-v /usr/local/bin/docker:/usr/bin/docker
Solution taken from this issue i opened: https://github.com/docker/for-win/issues/4642
Some containers (eg. portainer) work fine with -v /var/run/docker.sock:/var/run/docker.sock
The jenkins container required --user root permissions on the docker run command to successfully access the Docker UNIX socket (using Docker-Desktop on Windows).
By default, a unix domain socket (or IPC socket) is created at
/var/run/docker.sock, requiring either root permission, or docker
group membership.
Source: https://docs.docker.com/engine/reference/commandline/dockerd/#daemon-socket-option
--group-add docker had no effect using Docker-Desktop on Windows.
To bind to a Windows container you need to use pipes.
-v \\.\pipe\docker_engine:\\.\pipe\docker_engine
What it was suitable for me in Windows 10 was:
-v "\\.\pipe\docker_engine:\\.\pipe\docker_engine"
Have in mind that I was trying to access to portainer that I do recommend a lot it's a great app. For that I use this command:
docker run -d -p 9000:9000 -v "\\.\pipe\docker_engine:\\.\pipe\docker_engine" portainer/portainer
And then just go to:
http://localhost:9000/
I never made it worked myself, but i know it works on windows container on docker for windows server 2016 using this technique:
https://docs.docker.com/engine/reference/commandline/dockerd/#daemon-socket-option
We actually have at the shop vsts-agents on windows containers that uses the host docker like that:
# listen using the default unix socket, and on 2 specific IP addresses on this host.
$ sudo dockerd -H unix:///var/run/docker.sock -H tcp://192.168.59.106 -H tcp://10.10.10.2
# then you can execute remote docker commands (from container to host for example)
$ docker -H tcp://0.0.0.0:2375 ps
This is what actually made it work for me
docker run -p 8080:8080 -p 50000:50000 -v D:\docker-data\jenkins:/var/jenkins_home -v /usr/local/bin/docker:/usr/bin/docker -v /var/run/docker.sock:/var/run/docker.sock -u root jenkins/jenkins:lts
it works well :
docker run -it -v //var/run/docker.sock:/var/run/docker.sock -v /usr/local/bin/docker:/usr/bin/docker ubuntu

How to use --volume option with Docker Toolbox on Windows?

How can I share a folder between my Windows files and a docker container, by mounting a volume with simple --volume command using Docker Toolbox on?
I'm using "Docker Quickstart Terminal" and when I try this:
winpty docker run -it --rm --volume /C/Users/myuser:/myuser ubuntu
I have this error:
Invalid value "C:\\Users\\myuser\\:\\myuser" for flag --volume: bad mount mode specified : \myuser
See 'docker run --help'.
Following this, I also tried
winpty docker run -it --rm --volume "//C/Users/myuser:/myuser" ubuntu
and got
Invalid value "\\\\C:\\Users\\myuser\\:\\myuser" for flag --volume: \myuser is not an absolute path
See 'docker run --help'.
This is an improvement of the selected answer because that answer is limited to c:\Users folder. If you want to create a volume using a directory outside of c:\Users this is an extension.
In windows 7, I used docker toolbox. It used Virtual Box.
Open virtual box
Select the machine (in my case default).
Right clicked and select settings option
Go to Shared Folders
Include a new machine folder.
For example, in my case I have included:
**Name**: c:\dev
**Path**: c/dev
Click and close
Open "Docker Quickstart Terminal" and restart the docker machine.
Use this command:
$ docker-machine restart
To verify that it worked, following these steps:
SSH to the docker machine.
Using this command:
$ docker-machine ssh
Go to the folder that you have shared/mounted.
In my case, I use this command
$ cd /c/dev
Check the user owner of the folder. You could use "ls -all" and verify that the owner will be "docker"
You will see something like this:
docker#default:/c/dev$ ls -all
total 92
drwxrwxrwx 1 docker staff 4096 Feb 23 14:16 ./
drwxr-xr-x 4 root root 80 Feb 24 09:01 ../
drwxrwxrwx 1 docker staff 4096 Jan 16 09:28 my_folder/
In that case, you will be able to create a volume for that folder.
You can use these commands:
docker create -v /c/dev/:/app/dev --name dev image
docker run -d -it --volumes-from dev image
or
docker run -d -it -v /c/dev/:/app/dev image
Both commands work for me. I hope this will be useful.
This is actually an issue of the project and there are 2 working workarounds:
Creating a data volume:
docker create -v //c/Users/myuser:/myuser --name data hello-world
winpty docker run -it --rm --volumes-from data ubuntu
SSHing directly in the docker host:
docker-machine ssh default
And from there doing a classic:
docker run -it --rm --volume /c/Users/myuser:/myuser ubuntu
If you are looking for the solution that will resolve all the Windows issues and make it work on the Windows OS in the same way as on Linux, then see below. I tested this and it works in all cases. I’m showing also how I get it (the steps and thinking process). I've also wrote an article about using Docker and dealing with with docker issues here.
Solution 1: Use VirtualBox (if you think it's not good idea see Solution 2 below)
Open VirtualBox (you have it already installed along with the docker tools)
Create virtual machine
(This is optional, you can skip it and forward ports from the VM) Create second ethernet card - bridged, this way it will receive IP address from your network (it will have IP like docker machine)
Install Ubuntu LTS which is older than 1 year
Install docker
Add shared directories to the virtual machine and automount your project directories (this way you have access to the project directory from Ubuntu) but still can work in Windows
Done
Bonus:
Everything is working the same way as on Linux
Pause/Unpause the dockerized environment whenever you want
Solution 2: Use VirtualBox (this is very similar to the solution 1 but it shows also the thinking process, which might be usefull when solving similar issues)
Read that somebody move the folders to /C/Users/Public and that works https://forums.docker.com/t/sharing-a-volume-on-windows-with-docker-toolbox/4953/2
Try it, realize that it doesn’t have much sense in your case.
Read entire page here https://github.com/docker/toolbox/issues/607 and try all solutions listed on page
Find this page (the one you are reading now) and try all the solutions from other comments
Find somewhere information that setting COMPOSE_CONVERT_WINDOWS_PATHS=1 environment variable might solve the issue.
Stop looking for the solution for few months
Go back and check the same links again
Cry deeply
Feel the enlightenment moment
Open VirtualBox (you have it already installed along with the docker tools)
Create virtual machine with second ethernet card - bridged, this way it will receive IP address from your network (it will have IP like docker machine)
Install Ubuntu LTS which is very recent (not older than few months)
Notice that the automounting is not really working and the integration is broken (like clipboard sharing etc.)
Delete virtual machine
Go out and have a drink
Rent expensive car and go with high speed on highway
Destroy the car and die
Respawn in front of your PC
Install Ubuntu LTS which is older than 1 year
Try to run docker
Notice it’s not installed
Install docker by apt-get install docker
Install suggested docker.io
Try to run docker-compose
Notice it’s not installed
apt get install docker-compose
Try to run your project with docker-compose
Notice that it’s old version
Check your power level (it should be over 9000)
Search how to install latest version of docker and find the official guide https://docs.docker.com/install/linux/docker-ce/ubuntu/
Uninstall the current docker-compose and docker.io
Install docker using the official guide https://docs.docker.com/install/linux/docker-ce/ubuntu/
Add shared directories to the virtual machine and automount your project directories (this way you have access to the project directory from Ubuntu, so you can run any docker command)
Done
As of August 2016 Docker for windows now uses hyper-v directly instead of virtualbox, so I think it is a little different. First share the drive in settings then use the C: drive letter format, but use forward slashes. For instance I created an H:\t\REDIS directory and was able to see it mounted on /data in the container with this command:
docker run -it --rm -v h:/t/REDIS:/data redis sh
The same format, using drive letter and a colon then forward slashes for the path separator worked both from windows command prompt and from git bash.
I found this question googling to find an answer, but I couldn't find anything that worked. Things would seem to work with no errors being thrown, but I just couldn't see the data on the host (or vice-versa). Finally I checked out the settings closely and tried the format they show:
So first, you have to share the whole drive to the docker vm in settings here, I think that gives the 'docker-machine' vm running in hyper-v access to that drive. Then you have to use the format shown there, which seems to only exist in this one image and in no documentation or questions I could find on the web:
docker run --rm -v c:/Users:/data alpine ls /data
Simply using double leading slashes worked for me on Windows 7:
docker run --rm -v //c/Users:/data alpine ls /data/
Taken from here: https://github.com/moby/moby/issues/12590
Try this:
Open Docker Quickstart Terminal. If it is already open, run $ cd ~ to make sure you are in Windows user directory.
$ docker run -it -v /$(pwd)/ubuntu:/windows ubuntu
It will work if the error is due to typo. You will get an empty folder named ubuntu in your user directory. You will see this folder with the name windows in your ubuntu container.
For those using Virtual Box who prefer command-line approach
1) Make sure the docker-machine is not running
Docker Quickstart Terminal:
docker-machine stop
2) Create the sharing Windows <-> docker-machine
Windows command prompt:
(Modify following to fit your scenario. I feed my Apache httpd container from directory synced via Dropbox.)
set VBOX=D:\Program Files\Oracle\VirtualBox\VBoxManage.exe
set VM_NAME=default
set NAME=c/htdocs
set HOSTPATH=%DROPBOX%\htdocs
"%VBOX%" sharedfolder add "%VM_NAME%" --name "%NAME%" --hostpath "%HOSTPATH%" --automount
3) Start the docker-machine and mount the volume in a new container
Docker Quickstart Terminal:
(Again, I am starting an Apache httpd container, hence that port exposing.)
docker-machine start
docker run -d --name my-apache-container-0 -p 80:80 -v /c/htdocs:/usr/local/apache2/htdocs my-apache-image:1.0
share folders virtualBox toolbox and windows 7 and nodejs image container
using...
Docker Quickstart Terminal [QST]
Windows Explorer [WE]
lets start...
[QST] open Docker Quickstart Terminal
[QST] stop virtual-machine
$ docker-machine stop
[WE] open a windows explorer
[WE] go to the virtualBox installation dir
[WE] open a cmd and execute...
C:\Program Files\Oracle\VirtualBox>VBoxManage sharedfolder add "default" --name
"/d/SVN_FOLDERS/X2R2_WP6/nodejs" --hostpath "\?\d:\SVN_FOLDERS\X2R2_WP6\nodejs" --automount
check in the oracle virtual machine, that the new shared folder has appeared
[QST] start virtual-machine
$ docker-machine start
[QST] run container nodejs
docker stop nodejs
docker rm nodejs
docker run -d -it --rm --name nodejs -v /d/SVN_FOLDERS/X2R2_WP6/nodejs:/usr/src/app -w /usr/src/app node2
[QST] open bash to the container
docker exec -i -t nodejs /bin/bash
[QST] execute dir and you will see the shared files
I solved it!
Add a volume:
docker run -d -v my-named-volume:C:\MyNamedVolume testimage:latest
Mount a host directory:
docker run -d -v C:\Temp\123:C:\My\Shared\Dir testimage:latest

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