Container

Manipulation

ps

docker ps
- docker ps -a: list all the containers included the killed

run

Run

docker container run ubuntu:xenial /bin/bash: tell Docker which process to run inside container to replace default CMD, but nothing can be shown in the terminal
docker container run -it ubuntu:xenial: interactive mode, connect your terminal to the CT's bash shell
- Ctrl-PQ: exist and suspend the container
docker container run --name CT_Name ubuntu:xenial: name of the container
docker container run -it -d ubuntu:xenial: detached mode (executing as daemon in background)
docker container run -it --rm ubuntu:xenial: remove after the execution
docker container run -d -p 80:80 ubuntu:xenial: NAT the port
docker container run -d -P ubuntu:xenial: NAT port of the container to a random port of the host

Resource Limitation

docker run -m 200M --memory-swap=300M ubuntu
- -m 200M: memory
- --memory-swap 300M: memory+swap
docker run -it -m 200M --memory-swap=300M progrium/streee --vm 1 --vm-bytes 280M
- --vm 1: 1 process for the container
- --vm-bytes 280M: 280M memory for the process
docker run -c 1024 ubuntu
- -c 1024: CPU priority
docker run -it --blkio-weight 600
- --blkio-weight 600: disk input/output priority

attach/exec

docker attach: attach to the container's terminal
- docker attach CT_ID
docker exec: run a new process inside the container
- docker exec –it CT_ID /bin/bash: here it attaches a running container with a bash

stop/kill/start/restart

docker container start CT_ID: restart
docker container stop CT_ID: stop (send SIGTERM + SIGKILL)
docker container kill CT_ID: kill (send SIGKILL)

pause/unpause

docker pause CT_ID
docker unpause CT_ID

rm

docker container rm CT_ID: remove a stopped container
- docker container rm -f CT_ID: force mode, remove a running container
- docker container rm -f $(docker container ps -aq): remove all the containers

monitor

docker container ps
docker container top CT_ID
docker container top: real-time monitor
docker logs CT_ID
- docker logs -f CT_ID: continue to display new logs

Example

Manipulation

docker container run hello-world
docker container ps: we can't see the container hello-world
docker container ps -a: we can see all the containers including the stopped containers
docker container run -it --rm ubuntu:xenial /bin/bash
from another terminal docker container ps: what's the difference between the previous case? Why?
in the container
- ps aux
- exit or Ctrl-PQ: exit the container
- docker container ps -a
- docker container exec -it CT_ID /bin/bash

Web Server

docker container run -it --rm -p 8888:80 ubuntu:xenial
install and launch apache2 in the container
- apt update
- apt install apache2 vim
- vim /var/www/html/index.html
- apache2ctl -D FOREGROUND
access the web page from localhost:8888