Cannot get into a container namespace with bin/bash - bash

In one terminal I have a running container
docker container run --rm -it bash
In another terminal I want to run bin/bash in the same namespace as the running container above. For that to happen I followed these steps:
Grab the PID of the running container
docker inspect --format {{.State.Pid}} 32d7a757bc05
Let say the PID is 3386. When I run
sudo nsenter --target 3386 --mount --uts --ipc --net --pid bash
I get this error
nsenter: failed to execute bash: No such file or directory
But if I change bash to sh as below it works
sudo nsenter --target 3386 --mount --uts --ipc --net --pid sh
I'm on Centos 7, docker version 20.10.6 and as you have noticed I'm running my container from bash image. I cannot understand why bash is not working. Can someone please explain this?
Update
Just giving a little bit more background. I'm running my Centos as a Vagrant VM. I used vagrant ssh to connect to both terminals.
Vagrantfile
Vagrant.configure("2") do |config|
config.vm.box = "centos/7"
config.vm.provider "hyperv"
end

What you described actually worked for me:
sudo docker container run --rm -it bash
In a second terminal:
sudo nsenter --target 604861 --mount --uts --ipc --net --pid bash
bash-5.1# which bash
/usr/local/bin/bash
where I found the PID the way you described, using docker inspect --format {{.State.Pid}} CONTAINERID.

Related

Docker keeps complaining about the input device is not TTY

I'm using Windows-10 and using GitBash entering in the command
$ docker run -ti ubuntu:latest bash
And it gives me this error message
"the input device is not a TTY. If you are using mintty, try prefixing the command with 'winpty'"
And so I placed in this command to switch to winpty
$ winpty docker.exe run -it --rm ubuntu:14.04 /bin/bash
And it still doesn't work. I know my ports are running correctly, and I installed ubuntu correctly.
At windows 10 and git bash this works for me:
winpty docker exec -it "CONTAINTER ID" sh

Run command from .bashrc in detached docker container

I'm running a docker container in detached mode, and I'm having difficulty running a command that's in the container's ~/.bashrc.
Inside the docker container's ~/.bashrc:
labserve () {
jupyter lab --ip=0.0.0.0 --allow-root --no-browser --NotebookApp.token=''
}
If I start the container with
$ docker run -d image -p 8888:8888 --name jupyterbox
I'd like to be able to tell the image to tell the detached container to open up jupyterlab with the following command:
$ docker exec jupyterbox bash -c labserve
however, when I do that, I get the error
bash: labinit: command not found
On the other hand, if I do
$ docker run -it jupyterbox bash
root#4e344655fc31:/home# labserve
The command runs correctly, and opens up a jupyterlab within my docker container running on port 8888.
How do I exec this command in a detached container?

docker error on windows : the input device is not a TTY. If you are using mintty, try prefixing the command with 'winpty' [duplicate]

This question already has answers here:
Error "The input device is not a TTY"
(16 answers)
Closed 2 years ago.
After I run this
docker run --rm -v "/c/users/vipul rao/documents/github/wappalyzer:/opt/wappalyzer" -it wappalyzer/dev
I am getting the following error
the input device is not a TTY. If you are using mintty, try prefixing the command with 'winpty'
What should I use here? I am running Docker on Windows 8 in MINGW64.
As suggested by the error message you obtain, you should try to use winpty (which is installed by default with Git-Bash) and thus run:
winpty docker run --rm -v "/c/users/vipul rao/documents/github/wappalyzer:/opt/wappalyzer" -it wappalyzer/dev
If this works, you may want to set a Bash alias to avoid manually prepending winpty all the time:
echo "alias docker='winpty docker'" >> ~/.bashrc
or
echo "alias docker='winpty docker'" >> ~/.bash_profile
If you are using Git Bash you can try like this
winpty docker run -it ubuntu
This problem occurs when running with -it option using bash terminal on windows. You can use Powershell to resolve this issue.
This works for me.
I am using git bash on windows
winpty docker-compose exec app ls -l
Remove -it from the command. If you want to keep it interactive then keep -i
Don't use alias docker="winpty docker". It solves your problem but break pipes.
$ 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 .bashrc. This script uses winpty docker only if -ti is used.
function docker(){
for param; do if [[ "$param" == "-ti" ]] || [[ "$param" == "-it" ]]; then
winpty docker "$#"; return
fi; done;
command docker "$#"
}
docker run -ti ubuntu becomes winpty docker run -ti ubuntu avoids error: the input device is not a TTY. If you are using mintty, try prefixing the command with 'winpty'"
docker run ubuntu echo "what's up" | cat becomes command docker run echo "what'up" | cat avoids error: stdout is not a tty
The script only looks if there is a '-it' parameter without checking if it is inside a 'docker run' sentence... but it does the trick for my uses.
Did you start "Docker Quickstart Terminal"? I was trying to run
$ docker run -i -t redcricket/react-tutorial:latest /bin/bash
on windows from a Cygwin bash shell and got the same error:
the input device is not a TTY. If you are using mintty, try prefixing the command with 'winpty'
Then I remembered that when I installed docker on my windows 10 system something called "Docker Quickstart Terminal" got installed. You need to start that first from that dumb windows 'Type here to search' thing on the task bar:
That launches this …
… you can run your docker commands there without getting that error or running winpty.
The problem is with gitbash however with the powershell it is working fine ..
Happened to me. From Git Bash, on Windows 8 running Docker Toolbox. There are two things happening. From git bash, we do not seem to have complete escalated privilege to the docker daemon (even though i'm running git bash with administrative privileges).
Thus:
Try running the command from your docker terminal. (gives you privilege).
To compensate for errors from Window's folder naming formats, don't forget to quote the path.. (to escape spaces and/or capitalization errors) say
From:
docker run -v $(pwd):/data image_ref
To:
docker run -v "$(pwd):/data" image_ref
(notice the enclosing quotes in the latter around $(pwd):/data).
Just add 'winpty' in start of your cmd ,Try below:
$ winpty docker.exe run --rm -v "/c/users/vipul rao/documents/github/wappalyzer:/opt/wappalyzer" -it wappalyzer/dev
Why this happens? More details here:
http://willi.am/blog/2016/08/08/docker-for-windows-interactive-sessions-in-mintty-git-bash/
Got this error for running docker-compose exec workspace bash
So just prefix with winpty winpty docker-compose exec workspace bash
It may be that you're not running your commands within the Docker terminal. If you don't, you may not be properly connected to the Docker daemon and won't be able to interact correctly.
Make sure you're running commands in the actual Docker Terminal.
For those using WSL and running Docker for windows inside of cmder or conemu I would recommend to not to use Docker which is installed on windows in 'Program Files' but instead install Docker inside WSL on ubuntu/linux. Do remember though that you can't run Docker itself from within WSL, you must connect to Docker running on windows from the linux Docker client installed in WSL.
To install Docker on WSL
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
sudo apt-get update
sudo apt-get install docker-ce
Your options for running actual Docker commands are to either:
Connect to Docker using the switch -H
docker -H localhost:2375 run -it -v /mnt/c/code:/var/app -w "/var/app" centos:7
Or set the environment variable docker_host
export DOCKER_HOST=tcp://localhost:2375
Either way you are now be able to interactively connect to a running Docker container
you can try with Cmder tool it will work. Its not working with Gitbash
In addition to above mentioned solutions.
In case you are getting this error for docker attach
example: docker attach alpine1
error: the input device is not a TTY. If you are using mintty, try prefixing the command with 'winpty'
Solution: Adding winpty before docker command i.e. winpty docker attach should work.
example: winpty docker attach alpine1
Note: I was getting this error while using base on windows and this solution worked for me.
I had the same error when trying to run the docker-compose exec command.
In the help documentation docker-compose exec --help it shows how you can disable the pseudo-tty allocation by adding -T to your command options in the following way:
docker-compose exec -T
From the help documentation:
-T Disable pseudo-tty allocation. By default docker-compose exec allocates a TTY.
If you are using gitbash the problem is when setting the terminal emulator for for using with Git bash.setting the emurator
Instead you can change the emulator to the first options or use the
winpty command before your docker run command

Piping docker run container ID to docker exec

In my development, I find myself issuing a docker run command followed by a docker exec command on the resulting container ID quite frequently. It's a little annoying to have to copy/paste the container ID between commands, so I was trying to pipe the container ID into my docker exec command.
Here's my example command.
docker run -itd image | xargs -i docker exec -it {} bash
This starts the container, but then I get the following error.
the input device is not a TTY
Does anyone have any idea how to get around this?
Edit: I also forgot to mention I have an ENTRYPOINT defined and cannot override that.
Do this instead:
ID=$(docker run -itd image) && docker exec -it $ID bash
Because xargs executes it arguments without allocating a new tty.
If you just want to "bash"-into the container you do not have to pass the container-id around. You can simply run
docker run -it --rm <image> /bin/bash
For example, if we take the ubuntu base image
docker run -it --rm ubuntu /bin/bash
root#f80f83eec0d4:/#
from the documentation
-t : Allocate a pseudo-tty
-i : Keep STDIN open even if not attached
--rm : Automatically remove the container when it exits
The command /bin/bash overwrites the default command that is specified with the CMD instruction in the Dockerfile.

Docker. How to get bash\ssh inside runned container (run -d)?

I want to ssh or bash into runned docker container. Please, see example:
$ sudo docker run -d webserver
webserver is clean image from ubuntu:14.04
$ sudo docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
665b4a1e17b6 webserver:latest /bin/bash ... ... 22/tcp, 80/tcp loving_heisenberg
now I want to get something like this (go into runned container):
$ sudo docker run -t -i webserver (or maybe 665b4a1e17b6 instead)
$ root#665b4a1e17b6:/#
Previously I used Vagrant so I want to get behavior similar to vagrant ssh. Please, could anyone help me?
After the release of Docker version 1.3, the correct way to get a shell or other process on a running container is using the docker exec command. For example, you would run the following to get a shell on a running container:
docker exec -it myContainer /bin/bash
You can find more information in the documentation.
The answer is docker attach command.
For information see: https://askubuntu.com/a/507009/159189

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