Running additional command inside container

Attach to running container terminal

-it option

• -it option will attach container terminal to our host
• After that we can issue command directly to container.
• After that every command you issue will be inside the container.
• (Play around with some command)
• If you want to get out of the container you can exit the terminal.
• If default command in image is not shell, we can pass shell as @argument.
• docker run -it busybox /bin/sh

docker container exec

• docker container exec is used to execute command inside running container.
• docker container exec @id @command
• But we can use same option here -it and pass in shell as command. (Which is default for busybox)
• So docker container exec -it @id will attach container terminal to host.
• If you run ps aux inside the container, you can see sleep 5000 is a running process.

➜ docker container exec -it @id
/ # ps aux
PID   USER     TIME  COMMAND
    1 root      0:00 sleep 5000
    9 root      0:00 /bin/sh
   16 root      0:00 ps aux

Attach when starting stopped container

docker start -ia @name/@id

• If you want to attach the terminal, the option is bit different i.e -ia