Docker

command	Explanation
docker ps	Status of running containers
docker container ls	Status of running containers (As above)
docker run ubuntu	Run image ubuntu in containe (Terminates as its bash exits) - pull container if not present
docker run -d nginx	Run image nginx detach (as daemon stdin/stdout detached)
docker run -d -p 8080:80 nginx	Run image nginx detach (portmap redirect 8080->80) public to private - See rule with iptables -L -t nat -n or nft list ruleset
docker run -d -p 8080:80 -v /home/heth/nginx:/usr/share/nginx/html nginx	Same as above but with volume map. Actually mounts directory in container
docker run -it ubuntu	Run image ubuntu in container ( -it = interactive tty )
docker pull nginx	pull container from repository (default docker hub)
docker inspect 1e5bdae517e7	JSON dump of container config
docker container prune	Remove all stopped containers
docker exec -ti 1e5bdae517e7 bash	Run interactive bash in running container
docker attach 1e	attach your terminal's standard input, output, and error to a running container

Container preservation

root@ub1:~# docker run -it --name heth alpine
/ # echo "Hello, alpine" > hethfile.txt
/ #<CTRL-D>
root@ub1:~# docker start -ai heth
/ # cat hethfile.txt
Hello, alpine
/ #<CTRL-D>
root@ub1:~# docker rm heth

Running command in container

# echo "print("Hello, world")" > /tmp/hello.py
# docker run -it -v /tmp:/app python python3 /app/hello.py
Hello,world

Docker engine

Directories

/var/lib/docker

Base directory

• cgroups Linux
• namespaces Linux