I'm using an Alpine image in docker and I wanted to know if there is a command to open a new terminal and execute a command.
Like :
gnome-terminal -e <command>
I've already searched in ash man but didn't find what I wanted
You always have a choice of running commands on running containers irrespective of the OS type.
docker image pull nginx
docker container run -d --name nginx -p 80:80 nginx
docker exec -ti nginx sh -c "echo 'Hello World'"
Related
Any commands hang terminal inside docker container.
I login in container with docker exec -t php-zts /bin/bash
And then print any elementary command (date, ls, cd /, etc.)
Command hang
When I press ctrl+c I going back to host machine.
But, if I run any command without container - it's work normally
docker exec -t php-zts date
Wed Jan 26 00:04:38 UTC 2022
tty is enabled in docker-compose.yml
docker system prune and all cleanups can not help me.
I can't identify the problem and smashed my brain. Please help :(
The solution is to use the flag -i/--interactive with docker run. Here is a relevant section of the documentation:
--interactive , -i Keep STDIN open even if not attached
You can try to run your container using -i for interactive and -t for tty which will allow you to navigate and execute commands inside the container
docker run -it --rm alpine
In the other hand you can run the container with docker run then execute commands inside that container like so:
tail -f /dev/null will keep your container running.
-d will run the command in the background.
docker run --rm -d --name container1 alpine tail -f /dev/null
or
docker run --rm -itd --name container1 alpine sh # You can use -id or -td or -itd
This will allow you to run commands from inside the container.
you can choose sh, bash, or any other shell you prefer.
docker exec -it container1 alpine sh
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
I am running oracle-xe-11g on rancher os. I want to take the data backup of my DB. When I tried with the command
docker exec -it $Container_Name /bin/bash
then I entered:
exp userid=username/password file=test.dmp
It is working fine, and it created the test.dump file.
But I want to run the command with the docker exec command itself. When I tried this command:
docker exec $Container_Name sh -C exp userid=username/password file=test.dmp
I am getting this error message: sh: 0: Can't open exp.
The problem is:
When running bash with -c switch it is not running as interactive or a login shell so bash won't read the same startup scripts. Anything set in /etc/profile, ~/.bash_profile, ~/.bash_login, or ~/.profile would be skipped.
Workaround:
run your container with following command:
sudo docker run -d --name Oracle-DB -p 49160:22 -p 1521:1521 -e ORACLE_ALLOW_REMOTE=true -e ORACLE_HOME=/u01/app/oracle/product/11.2.0/xe -e PATH=/u01/app/oracle/product/11.2.0/xe/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin -e ORACLE_SID=XE -e SHLVL=1 wnameless/oracle-xe-11g
What I'm doing is specifying the environment variables set in the container using docker.
Now for generating the backup file:
sudo docker exec -it e0e6a0d3e6a9 /bin/bash -c "exp userid=system/oracle file=/test.dmp"
Please note the file will be created inside the container, so you need to copy it to docker host via docker cp command
This is how I did it. Mount a volume to the container e.g. /share/backups/ then execute:
docker exec -it oracle /bin/bash -c "ORACLE_HOME=/u01/app/oracle/product/11.2.0/xe ORACLE_SID=XE /u01/app/oracle/product/11.2.0/xe/bin/exp userid=<username>/<password> owner=<owner> file=/share/backups/$(date +"%Y%m%d")_backup.dmp"
I have got some docker container for instance my_container
I Want to run a long living script in my container, but not killing it while leaving the shell
I would like to do something like that
docker exec -ti my_container /bin/bash
And then
screen -S myScreen
Then
Executing my script in screen and exit the terminal
Unfortunately, I cannot execute screen in docker terminal
this maybe help you.
docker exec -i -t c2ab7ae71ab8 sh -c "exec >/dev/tty 2>/dev/tty </dev/tty && /usr/bin/screen -r nmsrv -s /bin/bash"
and this is the reference link
Only way I can think of is to run your container with your script at the start;
docker run -d --name my_container nginx /etc/init.d/myscript
If you have to run the script directly in an already running container, you can do that with exec:
docker exec my_container /path/to/some_script.sh
or if you wanna run it through Php:
docker exec my_container php /path/to/some_script.php
That said, you typically don't want to run scripts in already running containers, but to just use the same image as some already running container. You can do that with a standard docker run:
docker run -a stdout --rm some_repo/some_image:some_tag php /path/to/some_script.php
I'm running an apache server like this
docker run -d -p 80:80 php:apache /usr/sbin/apache2ctl -D FOREGROUNDD
Then I determine the name of the container with
docker ps
and execute an interactive shell on the container with
docker exec -ti hungry_fermi bash
It works well, but I would like to do the same in one command. I've tried
docker run -ti -d -p 80:80 php:apache /bin/bash -c 'bash; apache2ctl -D FOREGROUND'
The problem is that, I don't obtain a terminal and the command returns.
You're trying this:
docker run -ti -d -p 80:80 php:apache \
/bin/bash -c 'bash; apache2ctl -D FOREGROUND'
There are several problems here. First, you're using the -d command line option, which asks the docker client to detach and leave the container running. You will never get an interactive shell when using -d.
Secondly, your command -- bash; apache2ctl -D FOREGROUND -- would run bash, wait for bash to exit, then run httpd. You can instead do something like this:
docker run -ti -p 80:80 php:apache \
/bin/bash -c 'apachectl start; bash'
This would start Apache in the background (because there is no -D FOREGROUND), and then start bash...but I'm not really clear why you would want to do this, because now if you were to exit your shell the container would exit as well (taking Apache with it).
I think you are much better simply starting Apache the way you are now, and using docker exec to get a shell inside the container.