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Each time I want to access a docker container I have to run the command 

docker ps

The command show the id of the running container, after that, I have to copy the container id and use it in the following command :

docker exec -it /bin/bash

Is there a way to avoid searching for the container id each time I want to access that container.

Radwan Nizam
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4 Answers4

4

You can do docker exec with container name as well. for example 

root@qualys-virtual-machine:~/alpine-node-docker# docker ps
CONTAINER ID        IMAGE                                  COMMAND                  CREATED             STATUS              PORTS                    NAMES
fc5932f7ff9c        selenium/node-chrome:3.14.0-gallium    "/opt/bin/entry_poin…"   5 days ago          Up 5 days                                    root_chrome_3
8caa58ce6056        selenium/node-chrome:3.14.0-gallium    "/opt/bin/entry_poin…"   5 days ago          Up 5 days                                    root_chrome_5

now I can do docker exec with container names like root_chrome_3 

docker exec -it root_chrome_3 /bin/bash

to give name --name in run command.

janos
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Yash Jagdale
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3

I can use the folloiwng bash script :

#!/bin/bash
container_id=$(docker ps|grep <your container image name>|cut -d' ' -f1)
echo $container_id
cmd="docker exec -u 0 -it "$container_id" /bin/bash"
echo $cmd
exec $cmd

In my case, I stored the script in a file go_to_my_container.sh. You can run the following command to access your container:

sh go_to_my_container
Radwan Nizam
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    I believe `docker ps` has options to output the result in proper machine-readable format directly, though IIRC the formatting opions are pretty clunky. – tripleee Dec 12 '18 at 06:21
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    The script file name does not need to, and usually should not, have a `.sh` extension, and indeed, your `sh` command won't work if it does. A much better solution is to mark the script as executable and save it somewhere in your `PATH`. – tripleee Dec 12 '18 at 06:24
  • Finally, using `sh` to run a `bash` script is just wrong. https://stackoverflow.com/questions/5725296/difference-between-sh-and-bash – tripleee Dec 12 '18 at 06:26
2

You have to name your container and specify container name in the docker exec command, not image name.

So you have to add --name=CONTAINER_NAME into your docker run command and when you want to manage it just use docker exec -it CONTAINER_NAME bash.

If you use docker-compose to run your container, add container_name: CONTAINER_NAME under your service block to name it.

Example: 

version: '3.1'

services:
  server:
    image: nginx:latest
    container_name: nginx-server
    restart: always
    ports:
      - 80:80
Johnny Bui
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  • Good, I was not aware about 'container_name' in docker-compose . Thanks – Radwan Nizam Dec 12 '18 at 12:47
  • There is an issue with specifying the container name; based on docker-compose documentation: Because Docker container names must be unique, you cannot scale a service beyond 1 container if you have specified a custom name. Attempting to do so results in an error. (https://docs.docker.com/compose/compose-file/#cgroup_parent – Radwan Nizam Dec 13 '18 at 09:28
1

As you said that you need to copy container Id every time whenever you want to connect to that container is because either you haven't assigned any name to that container or it's picking up something default .

For Example : I am going to run a centOS image and want name it as dev-centos-1

You can write a docker file for this or run this following command to up your container 

docker container run --name dev-centos-1 -d centos:latest

once this container is up you can do everything by it's name :

docker stats dev-centos-1

docker logs dev-centos-1

or even connect to it bash :

docker exec -it dev-centos-1 bash

This is always considered as a better way to manage your containers in your environments .

Thanks .

Prabhat Singh
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