Docker – How to run docker container with bash shell

docker

It works with ubuntu image

wolf@linux:~$ docker run -it ubuntu /bin/bash
root@00e6296d31d8:/#

However, when I try it with different image such as vulnerables/web-dvwa, it doesn't work anymore

wolf@linux:~$ docker run -it vulnerables/web-dvwa /bin/bash
[+] Starting mysql...
[ ok ] Starting MariaDB database server: mysqld.
[+] Starting apache
[....] Starting Apache httpd web server: apache2AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 172.17.0.2. Set the 'ServerName' directive globally to suppress this message
. ok 
==> /var/log/apache2/access.log <==

==> /var/log/apache2/error.log <==
[Sat Apr 03 11:54:24.321232 2021] [mpm_prefork:notice] [pid 307] AH00163: Apache/2.4.25 (Debian) configured -- resuming normal operations
[Sat Apr 03 11:54:24.321280 2021] [core:notice] [pid 307] AH00094: Command line: '/usr/sbin/apache2'

==> /var/log/apache2/other_vhosts_access.log <==

id
whoami

There is no bash shell in this container

wolf@linux:~$ docker ps
CONTAINER ID   IMAGE                  COMMAND                CREATED          STATUS          PORTS     NAMES
820d3a292b2c   vulnerables/web-dvwa   "/main.sh /bin/bash"   11 seconds ago   Up 11 seconds   80/tcp    upbeat_visvesvaraya
wolf@linux:~$

Best Answer

You can attach to the container with:

 docker exec -ti 820d3a292b2c bash

or:

 docker exec -ti upbeat_visvesvaraya bash

Related Solutions

Docker – How to override CMD when running a docker image

You could just enter via docker run -it --entrypoint=/bin/bash $IMAGE -i (you 'll launch a new container from the image and get a bash shell in interactive mode), then run the entrypoint command in that container.

You can then inspect the running container in the state it should be running.

EDIT: Since Docker 1.3 you can use exec to run a process in a running container. Start your container as you 'd normally do, and then enter it by issuing:

docker exec -it $CONTAINER_ID /bin/bash

Assuming bash is installed you will be given shell access to the running container.

Docker – How to debug a docker container initialization

Docker events command may help and Docker logs command can fetch logs even after the image failed to start.

First start docker events in the background to see whats going on.

docker events&

Then run your failing docker run ... command. Then you should see something like the following on screen:

2015-12-22T15:13:05.503402713+02:00 xxxxxxxacd8ca86df9eac5fd5466884c0b42a06293ccff0b5101b5987f5da07d: (from xxx/xxx:latest) die

Then you can get the startup hex id from previous message or the output of the run command. Then you can use it with the logs command:

docker logs <copy the instance id from docker events messages on screen>

You should now see some output from the failed image startup.

As @alexkb suggested in a comment: docker events& can be troublesome if your container is being constantly restarted from something like AWS ECS service. In this scenario it may be easier to get the container hex id out of the logs in /var/log/ecs/ecs-agent.log.<DATE>. Then use docker logs <hex id>.

Best Answer

Related Solutions

Docker – How to override CMD when running a docker image

Docker – How to debug a docker container initialization

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