Testing and learning Docker with Azure
What do we get extra here:
- Python for programming
- Bash and linux, ssh, .sh scripts
- Azure VM with Docker, mount data drive, NSG
- Azure Container with Docker
Azure resources
https://follow-e-lo.com/2024/01/14/docker-be-efficient/
https://follow-e-lo.com/category/docker/
- docker run
- docker volume
- docker newtwork
- docker compose
- docker build
https://github.com/spawnmarvel/learning-docker/blob/main/1-getting-started-guide/README.md
https://github.com/spawnmarvel/learning-docker/blob/main/1.1-what-are-containers-john-s/Examples.sh
All examples bash
https://github.com/spawnmarvel/learning-docker/blob/main/1-what-are-containers-john-s/Examples.sh
Notes:
Controlling resources
- Linux control groups, cgroups (default to linux), how much cpu, memeory, blockio.
- Everything on linux lives in cgroup.
- Docker process within container running in own cgroup, meaning we an restrict all of this.
- And thats is, the cgroup can controll, check and controll the container.
# region Cgroups
# [...]
#starting deteched -d but interactive -it so bash has a terminal to attach to and not exit straight away
# Run new container with a name, detached/interactive,
# limit resources, use Ubuntu image and the container should run the bash process
docker run --name ubuntu -dit --memory=256m --cpus="2" ubuntu bashVisibility (isoloation) Namespaces
- Linux default also, can use name space.
# region Namespaces
38.00
For notes view readme
https://github.com/spawnmarvel/learning-docker/tree/main/1.2-dockerlabs
Docker Engine is an open source containerization technology for building and containerizing your applications
https://docs.docker.com/engine/
Update vm vmdocker01
# update vm
sudo apt update -y
sudo apt upgrade -y
Create script
# create script
touch add_repository_to_apt.sh
nano add_repository_to_apt.sh
#!/bin/bash
# Add Docker's official GPG key:
sudo apt update
sudo apt install ca-certificates curl gnupg
sudo install -m 0755 -d /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
sudo chmod a+r /etc/apt/keyrings/docker.gpg
# Add the repository to Apt sources:
echo \
"deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu \
$(. /etc/os-release && echo "$VERSION_CODENAME") stable" | \
sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
sudo apt-get update
Run it
sudo bash add_repository_to_apt.sh
Install the Docker packages
sudo apt install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-pluginVerify Docker Engine
sudo docker run hello-world
# Unable to find image 'hello-world:latest' locally
# latest: Pulling from library/hello-world
# xxxxxxxxxx: Pull complete
# Digest: sha256:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
# Status: Downloaded newer image for hello-world:latest
# Hello from Docker!
# This message shows that your installation appears to be working correctly.
# To generate this message, Docker took the following steps:
# 1. The Docker client contacted the Docker daemon.
# 2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
# (amd64)
# 3. The Docker daemon created a new container from that image which runs the
# executable that produces the output you are currently reading.
# 4. The Docker daemon streamed that output to the Docker client, which sent it
# to your terminal.
# To try something more ambitious, you can run an Ubuntu container with:
# $ docker run -it ubuntu bash
# Share images, automate workflows, and more with a free Docker ID:
# https://hub.docker.com/
# For more examples and ideas, visit:
# https://docs.docker.com/get-started/
docker --version
# Docker version 24.0.7, build afdd53bhttps://docs.docker.com/engine/install/ubuntu/
- cd /datadrive/
https://github.com/spawnmarvel/learning-docker/blob/main/README-0-mount.md
# login
ssh user@IP
# From above we ised sudo in front of docker, result without
docker run hello-world
# docker: permission denied while trying to connect to the Docker daemon socket
# Check if docker groups is present
getent group
getent group | grep docker
# docker:x:999:
# check if a user is in a group
id username
# Add the connected user "$USER" to the docker group. Change the user name to match your preferred user if you do not want to use your current user:
sudo gpasswd -a $USER docker
# Adding user username to group docker
# Activate, either do a newgrp docker or log out/in to activate the changes to groups.
newgrp docker
# Now run
docker run hello-world
# Hello from Docker!
# This message shows that your installation appears to be working correctly.
Use the docker prune’ command to clean up various Docker objects, freeing up system resources and making your Docker environment more efficient.
# To remove all stopped containers
docker container prune
# To remove all unused networks
docker network prune
# To remove all dangling images
docker image prune
# To remove all unused volumes
docker volume prune
# get all commands
docker
# help
docker COMMAND --help
docker system info
# https://www.digitalocean.com/community/tutorials/how-to-remove-docker-images-containers-and-volumes
# Docker provides a single command that will clean up any resources — images, containers, volumes, and networks — that are dangling (not tagged or associated with a container):
docker system prune
# To additionally remove any stopped containers and all unused images (not just dangling images), add the -a flag to the command:
docker system prune -a
# remove images
docker images -a
docker rmi -f id_name
docker rmi -f $(docker images -aq)
# remove containers
docker ps -a
docker rm -f id_name
docker rm $(docker ps -aq)
# remove volumes
docker volume ls
docker volume rm -f volume_name
# create the volume for presistent rmq, and pull rmq, start rmq
docker volume create rabbitmq_data
# the volume is on a mounted datadrive, view README-2-docker-volume.md, so we can separate os from data and even increase the disk.
sudo su -
cd /datadrive
# buildkit containers engine-id image network overlay2 plugins runtimes swarm tmp volumes
exit
df -h
# Filesystem Size Used Avail Use% Mounted on
# /dev/sda1 4.0G 702M 3.4G 18% /datadrive
# create the container for rmq
docker run -d --hostname rmq2 --name rabbitmq2 -p 15672:15672 -p 5672:5672 --mount type=volume,src=rabbitmq_data,target=/var/lib/rabbitmq rabbitmq:3.12-management
# view it
docker ps
docker images
# REPOSITORY TAG
# rabbitmq 3.12-management
# you can now stop and start the container with a volume
# or set it to always run
docker restart, stop, start rabbitmq2
# view logs
docker logs rabbitmq
docker logs -f rabbitmq
# 2024-01-01 15:47:03.330225+00:00 [info] <0.230.0> node : rabbit@rmq2
# 2024-01-01 15:47:03.330225+00:00 [info] <0.230.0> home dir : /var/lib/rabbitmq
# 2024-01-01 15:47:03.330225+00:00 [info] <0.230.0> config file(s) : /etc/rabbitmq/conf.d/10-defaults.conf
# 2024-01-01 15:47:03.330225+00:00 [info] <0.230.0> log(s) : <stdout>
# 2024-01-01 15:47:03.330225+00:00 [info] <0.230.0> data dir : /var/lib/rabbitmq/mnesia/rabbit@rmq2
# enter container, exit 13
docker exec -it rabbitmq2 bash
Volumes are a mechanism for storing data outside containers. All volumes are managed by Docker and stored in a dedicated directory on your host, usually /var/lib/docker/volumes for Linux systems.
# create the volume
docker volume create rabbitmq_data
# create the container
docker run -d --hostname rmq2 --name rabbitmq2 -p 15672:15672 -p 5672:5672 --mount type=volume,src=rabbitmq_data,target=/var/lib/rabbitmq rabbitmq:3.12-management
# veiw
docker volume ls
# remove not associated or used
docker volume prune
# In Docker, a "dangling" volume refers to a volume that is no longer associated with a container.
docker volume rm $(docker volume ls -qf dangling=true)https://follow-e-lo.com/2023/12/30/docker-volume-data-move/
Dockerfile
https://github.com/spawnmarvel/learning-docker/blob/main/README-1-dockerfile-reference
Layers
When you run a build, the builder attempts to reuse layers from earlier builds.
If a layer of an image is unchanged, then the builder picks it up from the build cache.
If a layer has changed since the last build, that layer, and all layers that follow, must be rebuilt.
FROM
WORKDIR
COPY
RUN download
COPY . .
RUN use the download
RUN
ENTRYPOINT ["PATH OR FILE", ARGS]It seems that it is already apart of the docker install from apt (install docker)
sudo apt update
sudo apt install docker-compose-plugin
# docker-compose-plugin is already the newest version (2.21.0-1~ubuntu.22.04~jammy).
docker compose version
Docker Compose version v2.21.0mkdir composetest
cd composetest
# for python code for example
sudo nano Dockerfile
sudo nano compose.yml
# If you want to run your services in the background, you can pass the -d flag (for "detached" mode) to docker compose up and use docker compose ps to see what is currently running:
docker compose up -d
docker compose up
# Switch to another terminal
docker images
docker image ls
docker inspect containername
docker logs containername
docker compose ps
# The docker compose run command allows you to run one-off commands for your services. For example, to see what environment variables are available to the web service:
docker compose run web env
# If you started Compose with docker compose up -d, stop your services once you've finished with them:
docker compose stop
# You can bring everything down, removing the containers entirely, with the down command.
docker compose down
# Pass --volumes to also remove the data volume used by the Redis container:
docker compose down --volumes
https://docs.docker.com/compose/compose-file/compose-file-v3/
https://learn.microsoft.com/en-us/azure/container-instances/container-instances-quickstart
https://learn.microsoft.com/en-us/azure/container-instances/container-instances-tutorial-prepare-app
https://learn.microsoft.com/en-us/training/modules/run-docker-with-azure-container-instances/
https://learn.microsoft.com/en-us/azure/container-instances/