Docker tutorial

Installing Docker on Ubuntu =

curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh

Docker Commands

docker run application
Run application, if it does not exist, it will pull it down

docker ps
list all running containers

docker ps -a
see all running container

docker stop
stop a container

docker rm
remove a container

docker images
list images locally

docker rmi nginx
will delete the image permanently

Persistent Data

if you create a mysql docker container and store everything in the container, when you delete the container everything will be lost 'To store the msql files outside the container , you would have to map the storage to an outside directory

docker run -v /opt/datadir:/var/lib/mysql mysql
this will mount the /opt/datadir to the internal /var/lib/mysql folder

docker pull nginx
will pull the nginx image down but not run it

docker exec nameofdockerinstance cat/etc/hosts
run a command withing the docker instance

run redis:4.0
run a specific version of a software

docker run -it ubuntu
run an app and attach to it terminal in an interactive mode

Port Mapping

Every docker container get's a local ip assigned (internal) you have top map the internal port to the external ip and port

docker run -p 80:5000 webapp
80 is the external port and 5000 is the internal port