If I spin up a Docker container with:
docker run -it ubuntu /bin/bash
and then exit. I can see the container using
docker ps -a
However, if I try and restart the container with
docker start <container ID>
I just get echoed back and returned to the command prompt.
What am I missing?
After running docker start <container ID> to restart the container try running a docker ps to ensure it's actually running.
If it IS running and you want to run commands on a bash shell from within the container, you can run the below command. In your case it would be :
docker exec -it <container ID> bash
use docker start with '-ai' so it attaches to container interactively
docker start -ai <container ID>
CAUTION! This will relaunch the process that this container is supposed to run:
If it is defined by a Dockerfile with a CMD instruction, then it will run it.
If it was a container for building a Dockerfile, the last failed instruction will be retried.
You can try:
docker start <container name>
Related
Why when i run the command
docker run ubuntu
without option '-it' is not possible to interact with the created container even when running command start with the -a -i options
docker start -a -i CONTAINER_ID
or when i run
docker start CONTAINER_ID
simply the container has the status "Exit (0) 4 seconds ago"
But when i run
docker run -it ubuntu
i can use bash shell of ubuntu using 'docker start -a -i'
When you run docker run without -it it's still running the container but you've not given it a command, so it finishes and exits.
If you try:
docker run ubuntu /bin/bash -c "echo 'hello'";
It'll run ubunu, then the command, and then finish because there is no reason for it to be kept alive afterwards.
-i is saying keep it alive and work within in the terminal (allow it to be interactive), but if you type exit, you're done and the container stops.
-t is showing the terminal of within the docker container (see: What are pseudo terminals (pty/tty)?)
-it allows you to see the terminal in the docker instance and interact with it.
Additionally you can use -d to run it in the background and then get to it afterwards.
Ex:
docker run -it -d --name mydocker ubuntu;
docker exec -it mydocker /bin/bash;
TLDR is -it allows you connect a terminal to interactively connect to the container.
If you run docker run --help, you can find the details about docker run options.
$ docker run --help
Usage: docker run [OPTIONS] IMAGE [COMMAND] [ARG...]
Run a command in a new container
Options:
...
-i, --interactive Keep STDIN open even if not attached
...
-t, --tty Allocate a pseudo-TTY
while starting a docker container I have to execute a script inside docker container. Can I do it using docker run command or docker start command mentioning the path in docker? I know I have to use CMD in docker file but dockerfile is not present
Have you tried
docker run -it <image-name> bash "command-to-execute"
To enter a running Docker container (get a Bash prompt inside the container), please run the following:
docker container exec -it <container_id> /bin/bash
You can get the container_id by listing running Docker containers with:
docker container ps -a or docker ps -a
docker run --name TEST -d image sh -c " CMD "
in CMD section you can give the path of shell script
Docker is not started even if the subsequent command is executed.
docker pull incendonet/centos7-mono-apache
Even if you check with docker ps, it does not exist.
Please tell me the cause.
Docker will be started after you run below command :
docker run -it -d image-name
docker run -it -d incendonet/centos7-mono-apache
docker pull command just fetches image from docker hub to your server/local machine. But to run it you need to use docker run.
Once it is running then it will be shown in your docker ps command and you can use below command to get into container's shell :
docker exec -it <container-id> /bin/bash
How to reboot centos in docker ?
I had pulled centos 7 from docker
use the 'shutdown -r now'
The console said 'Failed to talk to init daemon.'
I also used 'reboot -f' , and get the
'Rebooting.
Failed to reboot: Operation not permitted' for rsp
Why you want to restart container?
if it is necessary you can use
docker exec -it <container name> reboot
or you can stop container and start it again
docker stop -f <container name>
then
docker start <container name>
Assuming you are logged in to your container and trying to "reboot" the container:
e.g. docker run -i -t centos /bin/bash
and then reboot
You shouldn't do is.
Please use docker run/start/stop....
How can do something like:
docker exec -it 06a0076fb4c0 install-smt
But use the name of the container instead
docker exec -it container/container install-smt
I am running a build on CI server so I can not manually input the container ID.
How can I achieve this?
Yes, you can do this by naming the container with --name. Note that your command with container/container is likely referencing an image name and not the container.
➜ ~ docker run --name my_nginx -p 80:80 -d nginx
d122acc37d5bc2a5e03bdb836ca7b9c69670de79063db995bfd6f66b9addfcac
➜ ~ docker exec my_nginx hostname
d122acc37d5b
Although it won't save any typing, you can do something like this if you want to use the image name instead of giving the container a name:
docker run debian
docker exec -it `docker ps -q --filter ancestor=debian` bash
This will only work if you're only running one instance of the debian image.
It does help if you're constantly amending the image when working on a new Dockerfile, and wanting to repeatedly run the same command in each new container to check your changes worked as expected.
I was able to fix this by setting a container name in the docker-compose file, and rundocker exec -it with the name form the file.
#Héctor (tnx)
These steps worked for me:
This will start the container named mytapir and spawn a shell into the docker container:
docker run -d --name mytapir -it wsmoses/tapir-built:latest bash
Upon docker ps to ensure the docker container is running:
docker exec -it mytapir /bin/bash
Will spawned a shell into an existing container named mytapir.
And you can stop the container as usual docker stop mytapir.
And starting it via docker start mytapir, if it is not running.
(check via docker ps -a)