Working with basic Docker Commands

Play around with basic Docker Commands

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In this section, you will go through some of the commonly used Docker commands. These commands will you understand more about the functionalities of Docker and its ecosystem.

Basic Commands

Command	Description	Example
docker version	Show Docker version	docker version
docker info	Display system-wide information	docker info
docker pull	Pull docker image or repository from registry	docker pull alpine
docker images	List images	docker images
docker run	Run a command in a new container	docker run -it alpine sh
docker create	Create a new container	docker create -it alpine sh
docker exec	Run a command in running container	docker exec <container id/name> sh
docker ps	List containers	docker ps
docker inspect	Display information on Docker object	docker inspect <object id/name>
docker logs	Fetch the logs of a container	docker logs <container id/name>
docker stats	Display a live stream of container(s) resource usage	docker stats
docker network	Manage networks	docker network ls
docker rename	Rename a container	docker rename <old name> <new name>
docker stop	Stop one or more running containers	docker stop <container id/name> [or more]
docker rm	Remove one or more containers	docker rm <container id/name> [or more]
docker rmi	Remove one or more images	docker rmi <image id/name> [or more]
docker volume	Manage volumes	docker volume ls
docker build	Build an image from a Dockerfile	docker build -t image_name:v1 .

NOTE: Check the complete list of Docker CLI here.

Playing with Commands

Try running following commands and understand what is happening:

# List all images
$ docker images

# Pull Postgres latest image (debian based)
$ docker pull postgres

# Pull Postgres alpine image
$ docker pull postgres:13.4-alpine

# Run Postgres container based on latest image
$ docker run --name deb-postgres -e POSTGRES_PASSWORD=password -d postgres

# Run Postgres container based on alpine image
$ docker run --name alpine-postgres -e POSTGRES_PASSWORD=password -d postgres:13.4-alpine

# See all the running containers
$ docker ps

# Execute command on running container (run same for alpine-postgres)
$ docker exec -it deb-postgres bash
root@83b53844c490:/# su postgres
postgres@83b53844c490:/$ psql

# --- playaround with database ----
CREATE DATABASE dhanu; # create database
\c dhanu; # use database
CREATE TABLE users (
  person_id serial PRIMARY KEY,
  username VARCHAR(50) UNIQUE NOT NULL,
  password VARCHAR(50) NOT NULL,
  email  VARCHAR(255) UNIQUE NOT NULL
); # create users table
INSERT INTO users(username, password, email)
VALUES ('admin', 'admin123', 'admin@dhanugurung.com');
INSERT INTO users(username, password, email)
VALUES ('foo', 'foo123', 'foo@dhanugurung.com');
# --- end of playing ----

\q # exit from psql
exit # exit from postgres user
exit # exit from root

# Stop running container
$ docker stop alpine-postgres

# Seel all containers (exited as well)
$ docker ps -a

# Remove an exited container
$ docker stop alpine-postgres

# Remove a running container
$ docker stop deb-postgres

# See logs of a container
$ docker logs deb-postgres