Related
i'm trying to run the start command in docker after creating a container.
for example :
$ docker create busybox echo hi there
it gives me the id of that container like 4e59d0fe8584bb4dcaf44dbce100253b6767bf51546edc27f29f39f52ed57957
and when i try to start that container without any flags like: -a flag
it works, but it only gives me that id back again.
but when i try to show the output using the attach -a flag, actually nothing happened, even it didn't give me an error, simply the command still running without anything happened.
i also couldn't kill the command and stop the execution by Ctrl+c, so the only option i had to close the terminal
i tried to make the problem clear as possible as i can
You can run the image via this command:
docker run -it busybox
It goes you to shell environment and you have -i (interactive) -t (tty) terminal, which means you see the terminal.
The default CMD(PID1) for busybox image is sh, see this.
For docker create busybox echo hi there, the COMMAND becomes echo hi there. This means after container starts, it will first execute echo hi there, then as PID1 exit, the container exit too. If you use docker ps, you won't find your container, you could just find your exited container with docker ps -a.
So,
If you intend to run a one time task, then as the container finish its task, it's normal you could not enter into container anymore.
If you intend to run a daemon task, leave the container service there, you should choose a command which won't finish after run, then your container will still there.
For your case, to quick let you understand it, you could use next to have a quick understanding, use tail -f /dev/null to let the container not exit:
# docker create busybox sh -c "echo hi there; tail -f /dev/null"
840d7c972a96712e48c9aa391aa63638fb10e12307797e338157105bdfb6934e
root#shlava:~# docker start 840d7c972a96712e48c9aa391aa63638fb10e12307797e338157105bdfb6934e
840d7c972a96712e48c9aa391aa63638fb10e12307797e338157105bdfb6934e
root#shlava:~# docker logs 0ae2d689e63a8688213d1eaf285e555ba3d672b8953f0d2730a1897c9d648a26
hi there
root#shlava:~# docker exec -it 0ae2d689e63a8688213d1eaf285e555ba3d672b8953f0d2730a1897c9d648a26 /bin/sh
/ #
I'm studying the Docker documentation, but I'm having a hard time understanding the concept of creating a container, ssh, and ssh back.
I created a container with
docker run -ti ubuntu /bin/bash
Then, it starts the container and I can run commands. docker ps gives me
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
0e37da213a37 ubuntu "/bin/bash" About a minute ago Up About a minute keen_sammet
The issue is after I exit the container I can't ssh back.
I tried docker attach that gives me Error: No such container and I tried docker exec -ti <container>/bin/bash that gives me the same message Error: No such container
How do I run and ssh back to the container?
When you exit the bash process, the container exits (in general, a container will exit when the foreground process exits). The error message you are seeing is accurately describing the situation (the container is no longer running).
If you want to be able to docker exec into a container, you will want to run some sort of persistent command. For example, if you were to run:
docker run -ti -d --name mycontainer ubuntu bash
This would start a "detached" container. That means you've started bash, but it's just hanging around doing nothing. You could use docker exec to start a new process in this container:
$ docker exec -it mycontainer ps -fe
UID PID PPID C STIME TTY TIME CMD
root 1 0 0 16:28 pts/0 00:00:00 bash
root 17 0 0 16:28 pts/1 00:00:00 ps -fe
Or:
$ docker exec -it mycontainer bash
There's really no reason to start bash as the main process in this case, since you're not interacting with it. You can just as easily run...
docker run -ti -d --name mycontainer ubuntu sleep inf
...and the behavior would be the same.
The most common use case for all of this is when your docker run command starts up some sort of persistent service (like a web server, or a database server, etc), and then you use docker exec to perform diagnostic or maintenance tasks.
The docker attach command will re-connect you with the primary console of a detached container. In other words, if we return to the initial example:
docker run -ti -d --name mycontainer ubuntu bash
You could connect to that bash process (instead of starting a new one) by running:
docker attach mycontainer
At this point, exit would cause the container to exit.
First, you don't ssh to a docker container (unless you have a sshd process in that container). But you can execute a command with docker exec -ti mycontainer bash -l
But you can exec a command only on running container. If the container exited already you must use another approach : create an image from the container and run a new one.
Here is an example. First I create a container and create a file within then I exit it.
$ docker run -ti debian:9-slim bash -l
root#09f889e80153:/# echo aaaaaaaaaa > /zzz
root#09f889e80153:/# cat /zzz
aaaaaaaaaa
root#09f889e80153:/# exit
logout
As you can see the container is exited (Exited (0) 24 seconds ago)
$ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
09f889e80153 debian:9-slim "bash -l" 45 seconds ago Exited (0) 24 seconds ago thirsty_hodgkin
So I create a new image with docker commit
$ docker commit 09f889e80153 bla
sha256:6ceb88470326d2da4741099c144a11a00e7eb1f86310cfa745e8d3441ac9639e
So I can run a new container that contains previous container content.
$ docker run -ti bla bash -l
root#479a0af3d197:/# cat zzz
aaaaaaaaaa
I read my Docker container log output using
docker logs -f <container_name>
I log lots of data to the log in my node.js app via calls to console.log(). I need to clean the log, because it's gotten too long and the docker logs command first runs through the existing lines of the log before getting to the end. How do I clean it to make it short again? I'd like to see a command like:
docker logs clean <container_name>
But it doesn't seem to exist.
First, if you just need to see less output, you can have docker only show you the more recent lines:
docker logs --since 30s -f <container_name_or_id>
Or you can put a number of lines to limit:
docker logs --tail 20 -f <container_name_or_id>
To delete the logs on a Docker for Linux install, you can run the following for a single container:
echo "" > $(docker inspect --format='{{.LogPath}}' <container_name_or_id>)
Note that this requires root, and I do not recommend this. You could potentially corrupt the logfile if you null the file in the middle of docker writing a log to the same file. Instead you should configure docker to rotate the logs.
Lastly, you can configure docker to automatically rotate logs with the following in an /etc/docker/daemon.json file:
{
"log-driver": "json-file",
"log-opts": {"max-size": "10m", "max-file": "3"}
}
That allows docker to keep up to 3 log files per container, with each file limited to 10 megs (so a limit between 20 and 30 megs of logs per container). You will need to run a systemctl reload docker to apply those changes. And these changes are the defaults for any newly created container, they do not apply to already created containers. You will need to remove and recreate any existing containers to have these settings apply.
The best script I found is
sudo sh -c 'truncate -s 0 /var/lib/docker/containers/*/*-json.log'
It cleans all logs and you don't need to stop the containers.
Credit goes to https://bytefreaks.net/applications/docker/horrible-solution-how-to-delete-all-docker-logs
If you want to remove all log files, not only for a specific container's log, you can use:
docker system prune
But, note that this does not clear logs for running containers.
This is not the ideal solution, but until Docker builds in a command to do it, this is a good workaround.
Create a script file docker-clean-logs.sh with this content:
#!/bin/bash
rm $(docker inspect $1 | grep -G '"LogPath": "*"' | sed -e 's/.*"LogPath": "//g' | sed -e 's/",//g');
Grant the execute permission to it:
chmod +x ./docker-clean-logs.sh
Stop the Docker container that you want to clean:
docker stop <container_name>
Then run the above script:
./docker-clean-logs.sh <container_name>
And finally run your container again:
docker start ...
Credit goes to the user sgarbesi on this page: https://github.com/docker/compose/issues/1083
You can use logrotate as explained in this article
https://sandro-keil.de/blog/2015/03/11/logrotate-for-docker-container/
This needs to be done before launching the container.
Run:
docker inspect {containerId}
Copy LogPath value
truncate -s 0 {LogaPath}
Solution for a docker swarm service:
logging:
options:
max-size: "10m"
max-file: "10"
In order to do this on OSX, you need to get to the virtual machine the Docker containers are running in.
You can use the walkerlee/nsenter image to run commands inside the VM like so:
docker run --rm -it --privileged --pid=host walkerlee/nsenter -t 1 -m -u -i -n sh
Combining that with a simplified version of the accepted answer you get:
#!/bin/sh
docker run --rm -it --privileged --pid=host walkerlee/nsenter -t 1 -m -u -i -n \
cp /dev/null $(docker inspect -f '{{.LogPath}}' $1)
Save it, chmod +x it, run it.
As far as I can tell this doesn't require the container to be stopped. Also, it clears out the log file (instead of deleting it) avoiding errors when doing docker logs right after cleanup.
On Windows 10 none of the solutions worked for me, I kept getting 'No such file or directory'
This worked
Get container ID (inspect the container)
In file explorer open docker-desktop-data (in WSL)
Navigate to version-pack-data\community\docker\containers\CONTAINER_ID
Stop the container
Open the file CONTAINER_ID-json.log file and trim it or just create a blank file with same name
source
According to tutorial I read so far, use "docker run -d" will start a container from image, and the container will run in background. This is how it looks like, we can see we already have container id.
root#docker:/home/root# docker run -d centos
605e3928cdddb844526bab691af51d0c9262e0a1fc3d41de3f59be1a58e1bd1d
But if I ran "docker ps", nothing was returned.
So I tried "docker ps -a", I can see container already exited:
root#docker:/home/root# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
605e3928cddd centos:latest "/bin/bash" 31 minutes ago Exited (0) 31 minutes ago kickass_swartz
Anything I did wrong? How can I troubleshoot this issue?
The centos dockerfile has a default command bash.
That means, when run in background (-d), the shell exits immediately.
Update 2017
More recent versions of docker authorize to run a container both in detached mode and in foreground mode (-t, -i or -it)
In that case, you don't need any additional command and this is enough:
docker run -t -d centos
The bash will wait in the background.
That was initially reported in kalyani-chaudhari's answer and detailed in jersey bean's answer.
vonc#voncvb:~$ d ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
4a50fd9e9189 centos "/bin/bash" 8 seconds ago Up 2 seconds wonderful_wright
Note that for alpine, Marinos An reports in the comments:
docker run -t -d alpine/git does not keep the process up.
Had to do: docker run --entrypoint "/bin/sh" -it alpine/git
Original answer (2015)
As mentioned in this article:
Instead of running with docker run -i -t image your-command, using -d is recommended because you can run your container with just one command and you don’t need to detach terminal of container by hitting Ctrl + P + Q.
However, there is a problem with -d option. Your container immediately stops unless the commands keep running in foreground.
Docker requires your command to keep running in the foreground. Otherwise, it thinks that your applications stops and shutdown the container.
The problem is that some application does not run in the foreground. How can we make it easier?
In this situation, you can add tail -f /dev/null to your command.
By doing this, even if your main command runs in the background, your container doesn’t stop because tail is keep running in the foreground.
So this would work:
docker run -d centos tail -f /dev/null
Or in Dockerfile:
ENTRYPOINT ["tail"]
CMD ["-f","/dev/null"]
A docker ps would show the centos container still running.
From there, you can attach to it or detach from it (or docker exec some commands).
According to this answer, adding the -t flag will prevent the container from exiting when running in the background. You can then use docker exec -i -t <image> /bin/bash to get into a shell prompt.
docker run -t -d <image> <command>
It seems that the -t option isn't documented very well, though the help says that it "allocates a pseudo-TTY."
Background
A Docker container runs a process (the "command" or "entrypoint") that keeps it alive. The container will continue to run as long as the command continues to run.
In your case, the command (/bin/bash, by default, on centos:latest) is exiting immediately (as bash does when it's not connected to a terminal and has nothing to run).
Normally, when you run a container in daemon mode (with -d), the container is running some sort of daemon process (like httpd). In this case, as long as the httpd daemon is running, the container will remain alive.
What you appear to be trying to do is to keep the container alive without a daemon process running inside the container. This is somewhat strange (because the container isn't doing anything useful until you interact with it, perhaps with docker exec), but there are certain cases where it might make sense to do something like this.
(Did you mean to get to a bash prompt inside the container? That's easy! docker run -it centos:latest)
Solution
A simple way to keep a container alive in daemon mode indefinitely is to run sleep infinity as the container's command. This does not rely doing strange things like allocating a TTY in daemon mode. Although it does rely on doing strange things like using sleep as your primary command.
$ docker run -d centos:latest sleep infinity
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
d651c7a9e0ad centos:latest "sleep infinity" 2 seconds ago Up 2 seconds nervous_visvesvaraya
Alternative Solution
As indicated by cjsimon, the -t option allocates a "pseudo-tty". This tricks bash into continuing to run indefinitely because it thinks it is connected to an interactive TTY (even though you have no way to interact with that particular TTY if you don't pass -i). Anyway, this should do the trick too:
$ docker run -t -d centos:latest
Not 100% sure whether -t will produce other weird interactions; maybe leave a comment below if it does.
Hi this issue is because docker containers exit if there is no running application in the container.
-d
option is just to run a container in deamon mode.
So the trick to make your container continuously running is point to a shell file in docker which will keep your application running.You can try with a start.sh file
Eg: docker run -d centos sh /yourlocation/start.sh
This start.sh should point to a never ending application.
In case if you dont want any application to be running,you can install monit which will keep your docker container running.
Please let us know if these two cases worked for you to keep your container running.
All the best
You can accomplish what you want with either:
docker run -t -d <image-name>
or
docker run -i -d <image-name>
or
docker run -it -d <image-name>
The command parameter as suggested by other answers (i.e. tail -f /dev/null) is completely optional, and is NOT required to get your container to stay running in the background.
Also note the Docker documentation suggests that combining -i and -t options will cause it to behave like a shell.
See:
https://docs.docker.com/engine/reference/run/#foreground
I have this code snippet run from the ENTRYPOINT in my docker file:
while true
do
echo "Press [CTRL+C] to stop.."
sleep 1
done
Run the built docker image as:
docker run -td <image name>
Log in to the container shell:
docker exec -it <container id> /bin/bash
execute command as follows :
docker run -t -d <image-name>
if you want to specify port then command as below:
docker run -t -d -p <port-no> <image-name>
verify the running container using following command:
docker ps
Docker container exits if task inside is done, so if you want to keep it alive even if it does not have any job or already finished them, you can do docker run -di image. After you do docker container ls you will see it running.
Docker requires your command to keep running in the foreground. Otherwise, it thinks that your applications stops and shutdown the container.
So if your docker entry script is a background process like following:
/usr/local/bin/confd -interval=30 -backend etcd -node $CONFIG_CENTER &
The '&' makes the container stop and exit if there are no other foreground process triggered later.
So the solution is just remove the '&' or have another foreground CMD running after it, such as
tail -f server.log
If you are using CMD at the end of your Dockerfile, what you can do is adding the code at the end. This will only work if your docker is built on ubuntu, or any OS that can use bash.
&& /bin/bash
Briefly the end of your Dockerfile will look like something like this.
...
CMD ls && ... && /bin/bash
So if you have anything running automatically after you run your docker image, and when the task is complete the bash terminal will be active inside your docker. Thereby, you can enter you shell commands.
Maybe it is just me but on CentOS 7.3.1611 and Docker 1.12.6 but I ended up having to use a combination of the answers posted by #VonC & #Christopher Simon to get this working reliably. Nothing I did before this would stop the container from exiting after it ran CMD successfully. I am starting oracle-xe-11Gr2 and sshd.
Dockerfile
...
RUN ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key -N '' && systemctl enable sshd
...
CMD /etc/init.d/oracle-xe start && /sbin/sshd && tail -f /dev/null
Then adding -d -t and -i to run
docker run --shm-size=2g --name oracle-db -d -t -i -p 5022:22 -p 5080:8080 -p 1521:1521 centos-oracle:7.3.1611
Finally after hours of bashing my head against the wall
ssh -v root#127.0.0.1 -p 5022
...
root#127.0.0.1's password:
debug1: Authentication succeeded (password).
For whatever reason the above will exit after executing CMD if the tail -f is removed, or any of the -t -d -i options are omitted.
I had the same issue, just opening another terminal with a bash on it worked for me :
create container:
docker run -d mcr.microsoft.com/mssql/server:2019-CTP3.0-ubuntu
containerid=52bbc9b30557
start container:
docker start 52bbc9b30557
start bash to keep container running:
docker exec -it 52bbc9b30557 bash
start process you need:
docker exec -it 52bbc9b30557 /path_to_cool_your_app
Running docker with interactive mode might solve the issue.
Here is the example for running image with and without interactive mode
chaitra#RSK-IND-BLR-L06:~/dockers$ sudo docker run -d -t -i test_again1.0
b6b9a942a79b1243bada59db19c7999cfff52d0a8744542fa843c95354966a18
chaitra#RSK-IND-BLR-L06:~/dockers$ sudo docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
chaitra#RSK-IND-BLR-L06:~/dockers$ sudo docker run -d -t -i test_again1.0 bash
c3d6a9529fd70c5b2dc2d7e90fe662d19c6dad8549e9c812fb2b7ce2105d7ff5
chaitra#RSK-IND-BLR-L06:~/dockers$ sudo docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
c3d6a9529fd7 test_again1.0 "bash" 2 seconds ago Up 1 second awesome_haibt
You can simply use:
docker container run -d -it <container name or id> /bin/bash
I have explained it in the following post that has the same question.
How to retain docker alpine container after "exit" is used?
I was also facing the same problem but in a different manner. When I create the docker containers. it automatically stops the unused containers which are just running in the background. Sometimes it also stops the containers that are in the use.
In my situation, this is because of the permission of the docker.sock files it earlier has.
what you have to do is :-
Install docker again.(As i work on ubuntu i install it from here)
Run the command to change the permissions.
sudo chmod 666 /var/run/docker.sock
Install docker-compose (this is optional as I have compose file to create many containers together)
sudo curl -L "https://github.com/docker/compose/releases/download/1.26.0/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
sudo chmod +x /usr/local/bin/docker-compose
check for the version to ensure that I have the latest one and not get problem with some deprications.
Then I run the docker container build.
Argument order matters
Jersey Beans answer (all 3 examples) worked for me. After quite a bit of trial and error I realized that the order of the arguments matter.
Keeps the container running in the background:
docker run -t -d <image-name>
Keeps the container running in the foreground: docker run <image-name> -t -d
It wasn't obvious to me coming from a Powershell background.
if you want to operate on the container, you need to run it in foreground to keep it alive.
There are multiple options out there to run the container in foreground/detached state. But if you still feel the issue is not resolved, you can try troubleshooting the issue by viewing the logs.
sudo docker logs -f >> container.log
additionally you can also use --details to show extra details provided to logs.
Incorrect Path to App in Dockerfile:
I was migrating an application from a RHEL server to a Docker container using Alpine Linux.
No errors during the build, so I was surprised to see the container immediately exit!
First port of call:
docker logs <containerID>
This revealed the path of the binary I had supplied to CMD in the Dockerfile was bogus:
line 0: /sbin/postfix: not found
Well that told me how things were broken, but not specifically where: I still required the correct path for the binary in Alpine Linux...
Troubleshooting:
Googling didn't reveal the correct path to it, so I added the following line to my Dockerfile:
RUN which postfix
I then reviewed my build logging- provided by the below command appended to my build command- to retrieve the value of RUN which postfix
--progress=plain > /path/to/build.log 2>&1
The Fix:
I deleted this test build, supplied the correct path- /usr/sbin/postfix - to CMD in the Dockerfile, deleted RUN which postfix and ran another build.
Voila; the process now remained up.
So a duff path was causing the container to immediately exit...
These 4 commands all work to keep your docker container running:
docker run -td centos
docker run -dt centos
docker run -t -d centos
docker run -d -t centos
Firstly, You need to check if any container is running
Type command,
docker ps -all
If any container is running then stop them
Type command,
docker stop Container Id
Now, Finally run the docker by using below command..........
docker run -t -p 2020:3000 dockerImageName
Hence, Open your google chrome and visit on localhost:2020
Congrats :)
I created a container with -d so it's not interactive.
docker run -d shykes/pybuilder bin/bash
I see that the container has exited:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
d6c45e8cc5f0 shykes/pybuilder:latest "bin/bash" 41 minutes ago Exited (0) 2 seconds ago clever_bardeen
Now I would like to run occasional commands on the machine and exit. Just to get the response.
I tried to start the machine. I tried attaching. I thought I could call run with a container, but that does not seem to be allowed. Using start just seems to run and then exist quickly.
I'd like to get back into interactive mode after exiting.
I tried:
docker attach d6c45e8cc5f0
But I get:
2014/10/01 22:33:34 You cannot attach to a stopped container, start it first
But if I start it, it exits anyway. Catch 22. I can't win.
In October 2014 the Docker team introduced docker exec command: https://docs.docker.com/engine/reference/commandline/exec/
So now you can run any command in a running container just knowing its ID (or name):
docker exec -it <container_id_or_name> echo "Hello from container!"
Note that exec command works only on already running container. If the container is currently stopped, you need to first run it with the following command:
docker run -it -d shykes/pybuilder /bin/bash
The most important thing here is the -d option, which stands for detached. It means that the command you initially provided to the container (/bin/bash) will be run in the background and the container will not stop immediately.
Your container will exit as the command you gave it will end. Use the following options to keep it live:
-i Keep STDIN open even if not attached.
-t Allocate a pseudo-TTY.
So your new run command is:
docker run -it -d shykes/pybuilder bin/bash
If you would like to attach to an already running container:
docker exec -it CONTAINER_ID /bin/bash
In these examples /bin/bash is used as the command.
So I think the answer is simpler than many misleading answers above.
To start an existing container which is stopped
docker start <container-name/ID>
To stop a running container
docker stop <container-name/ID>
Then to login to the interactive shell of a container
docker exec -it <container-name/ID> bash
To start an existing container and attach to it in one command
docker start -ai <container-name/ID>
Beware, this will stop the container on exit. But in general, you need to start the container, attach and stop it after you are done.
To expand on katrmr's answer, if the container is stopped and can't be started due to an error, you'll need to commit it to an image. Then you can launch bash in the new image:
docker commit [CONTAINER_ID] temporary_image
docker run --entrypoint=bash -it temporary_image
Some of the answers here are misleading because they concern containers that are running, not stopped.
Sven Dowideit explained on the Docker forum that containers are bound to their process (and Docker can't change the process of a stopped container, seemingly due at least to its internal structure: https://github.com/docker/docker/issues/1437). So, basically the only option is to commit the container to an image and run it with a different command.
See https://forums.docker.com/t/run-command-in-stopped-container/343
(I believe the "ENTRYPOINT with arguments" approach wouldn't work either, since you still wouldn't be able to change the arguments to a stopped container.)
I had to use bash -c to run my command:
docker exec -it CONTAINER_ID bash -c "mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql mysql"
Creating a container and sending commands to it, one by one:
docker create --name=my_new_container -it ubuntu
docker start my_new_container
// ps -a says 'Up X seconds'
docker exec my_new_container /path/to/my/command
// ps -a still says 'Up X+Y seconds'
docker exec my_new_container /path/to/another/command
If you are trying to run shell script, you need run it as bash.
docker exec -it containerid bash -c /path/to/your/script.sh
This is a combined answer I made up using the CDR LDN answer above and the answer I found here.
The following example starts an Arch Linux container from an image, and then installs git on that container using the pacman tool:
sudo docker run -it -d archlinux /bin/bash
sudo docker ps -l
sudo docker exec -it [container_ID] script /dev/null -c "pacman -S git --noconfirm"
That is all.
Pipe a command to docker exec bash stdin
Must remove the -t for it to work:
echo 'touch myfile' | docker exec -i CONTAINER_NAME bash
This can be more convenient that using CLI options sometimes.
Tested with:
docker run --name ub16 -it ubuntu:16.04 bash
then on another shell:
echo 'touch myfile' | docker exec -i ub16 bash
Then on first shell:
ls -l myfile
Tested on Docker 1.13.1, Ubuntu 16.04 host.
I would like to note that the top answer is a little misleading.
The issue with executing docker run is that a new container is created every time. However, there are cases where we would like to revisit old containers or not take up space with new containers.
(Given clever_bardeen is the name of the container created...)
In OP's case, make sure the docker image is first running by executing the following command:
docker start clever_bardeen
Then, execute the docker container using the following command:
docker exec -it clever_bardeen /bin/bash
I usually use this:
docker exec -it my-container-name bash
to continuously interact with a running container.
Assuming the image is using the default entrypoint /bin/sh -c, running /bin/bash will exit immediately in daemon mode (-d). If you want this container to run an interactive shell, use -it instead of -d. If you want to execute arbitrary commands in a container usually executing another process, you might want to try nsenter or nsinit. Have a look at https://blog.codecentric.de/en/2014/07/enter-docker-container/ for the details.
Unfortunately it is impossible to override ENTRYPOINT with arguments with docker run --entrypoint to achieve this goal.
Note: you can override the ENTRYPOINT setting using --entrypoint, but
this can only set the binary to exec (no sh -c will be used).
For Mac:
$ docker exec -it <container-name> sh
if you want to connect as root user:
$ docker exec -u 0 -it <container-name> sh
Simple answer: start and attach at the same time. In this case you are doing exactly what you asked for.
docker start <CONTAINER_ID/CONTAINER_NAME> && docker attach <CONTAINER_ID/CONTAINER_NAME>
make sure to change <CONTAINER_ID/CONTAINER_NAME>
I am running windows container and I need to look inside the docker container for files and folder created and copied.
In order to do that I used following docker entrypoint command to get the command prompt running inside the container or attach to the container.
ENTRYPOINT ["C:\\Windows\\System32\\cmd.exe", "-D", "FOREGROUND"]
That helped me both to the command prompt attach to container and to keep the container a live. :)
# docker exec -d container_id command
Ex:
# docker exec -d xcdefrdtt service jira stop
A quick way to resume and access the most recently exited container:
docker start -a -i `docker ps -q -l`
An easy solution that solved a similar problem for me:
docker run --interactive --tty <name_of_image>