What does docker-ce-cli & containerd.io installation packages install?
But the documentation mentions installation instruction as:
Is docker-ce an installation package for docker daemon/server/engine(only)?
Is docker-ce-cli an installation package to install docker client(only)?
Is containerd.io an installation package to install containerd component in below architecture?
1 Answer 1
Is docker-ce an installation package for docker daemon/server/engine(only)?
Is docker-ce-cli an installation package to install docker client(only)?
Is containerd.io an installation package to install containerd component in below architecture?
Yes to all of those. The architecture diagram is pretty clear. Docker itself used to implement all of this into a single binary, but overtime they decided to embrace the Open Container Initiative (OCI).
containerd is one implementation that follows the OCI. It uses kernel features to provide a runtime environment for containers.
dockerd talks to containerd and also provides more features to Docker users in the form of the easy commands like docker build , docker network , docker volume and docker inspect .
docker-cli provides the docker binary client that talks to the dockerd API, on a local socket or remotely. Even without this client, you could still build and run containers by just using the API.
Install Docker Engine on Ubuntu
To get started with Docker Engine on Ubuntu, make sure you meet the prerequisites, then install Docker.
Prerequisites
OS requirements
To install Docker Engine, you need the 64-bit version of one of these Ubuntu versions:
- Ubuntu Kinetic 22.10
- Ubuntu Jammy 22.04 (LTS)
- Ubuntu Focal 20.04 (LTS)
- Ubuntu Bionic 18.04 (LTS)
Docker Engine is compatible with x86_64 (or amd64 ), armhf , arm64 , and s390x architectures.
Uninstall old versions
Older versions of Docker went by the names of docker , docker.io , or docker-engine . Uninstall any such older versions before attempting to install a new version:
It’s OK if apt-get reports that none of these packages are installed.
Images, containers, volumes, and networks stored in /var/lib/docker/ aren’t automatically removed when you uninstall Docker. If you want to start with a clean installation, and prefer to clean up any existing data, refer to the uninstall Docker Engine section.
Installation methods
You can install Docker Engine in different ways, depending on your needs:
Docker Engine comes bundled with Docker Desktop for Linux. This is the easiest and quickest way to get started.
You can also set up and install Docker Engine from Docker’s apt repository.
Install it manually and manage upgrades manually.
Using a convenience scripts. Only recommended for testing and development environments.
Install using the repository
Before you install Docker Engine for the first time on a new host machine, you need to set up the Docker repository. Afterward, you can install and update Docker from the repository.
Set up the repository
Update the apt package index and install packages to allow apt to use a repository over HTTPS:
Add Docker’s official GPG key:
Use the following command to set up the repository:
Install Docker Engine
Update the apt package index:
Receiving a GPG error when running apt-get update ?
Your default umask may be incorrectly configured, preventing detection of the repository public key file. Try granting read permission for the Docker public key file before updating the package index:
Install Docker Engine, containerd, and Docker Compose.
To install the latest version, run:
To install a specific version of Docker Engine, start by list the available versions in the repository:
Select the desired version and install:
Verify that the Docker Engine installation is successful by running the hello-world image:
This command downloads a test image and runs it in a container. When the container runs, it prints a confirmation message and exits.
You have now successfully installed and started Docker Engine. The docker user group exists but contains no users, which is why you’re required to use sudo to run Docker commands. Continue to Linux post-install to allow non-privileged users to run Docker commands and for other optional configuration steps.
Upgrade Docker Engine
To upgrade Docker Engine, follow the installation instructions, choosing the new version you want to install.
Install from a package
If you can’t use Docker’s apt repository to install Docker Engine, you can download the deb file for your release and install it manually. You need to download a new file each time you want to upgrade Docker Engine.
Select your Ubuntu version in the list.
Go to pool/stable/ and select the applicable architecture ( amd64 , armhf , arm64 , or s390x ).
Download the following deb files for the Docker Engine, CLI, containerd, and Docker Compose packages:
- containerd.io_<version>_<arch>.deb
- docker-ce_<version>_<arch>.deb
- docker-ce-cli_<version>_<arch>.deb
- docker-buildx-plugin_<version>_<arch>.deb
- docker-compose-plugin_<version>_<arch>.deb
Install the .deb packages. Update the paths in the following example to where you downloaded the Docker packages.
The Docker daemon starts automatically.
Verify that the Docker Engine installation is successful by running the hello-world image:
This command downloads a test image and runs it in a container. When the container runs, it prints a confirmation message and exits.
You have now successfully installed and started Docker Engine. The docker user group exists but contains no users, which is why you’re required to use sudo to run Docker commands. Continue to Linux post-install to allow non-privileged users to run Docker commands and for other optional configuration steps.
Upgrade Docker Engine
To upgrade Docker Engine, download the newer package file and repeat the installation procedure, pointing to the new file.
Install using the convenience script
Docker provides a convenience script at https://get.docker.com/ to install Docker into development environments non-interactively. The convenience script isn’t recommended for production environments, but it’s useful for creating a provisioning script tailored to your needs. Also refer to the install using the repository steps to learn about installation steps to install using the package repository. The source code for the script is open source, and can be found in the docker-install repository on GitHub.
Always examine scripts downloaded from the internet before running them locally. Before installing, make yourself familiar with potential risks and limitations of the convenience script:
- The script requires root or sudo privileges to run.
- The script attempts to detect your Linux distribution and version and configure your package management system for you.
- The script doesn’t allow you to customize most installation parameters.
- The script installs dependencies and recommendations without asking for confirmation. This may install a large number of packages, depending on the current configuration of your host machine.
- By default, the script installs the latest stable release of Docker, containerd, and runc. When using this script to provision a machine, this may result in unexpected major version upgrades of Docker. Always test upgrades in a test environment before deploying to your production systems.
- The script isn’t designed to upgrade an existing Docker installation. When using the script to update an existing installation, dependencies may not be updated to the expected version, resulting in outdated versions.
Tip: preview script steps before running
You can run the script with the —dry-run option to learn what steps the script will run when invoked:
This example downloads the script from https://get.docker.com/ and runs it to install the latest stable release of Docker on Linux:
You have now successfully installed and started Docker Engine. The docker service starts automatically on Debian based distributions. On RPM based distributions, such as CentOS, Fedora, RHEL or SLES, you need to start it manually using the appropriate systemctl or service command. As the message indicates, non-root users can’t run Docker commands by default.
Use Docker as a non-privileged user, or install in rootless mode?
The installation script requires root or sudo privileges to install and use Docker. If you want to grant non-root users access to Docker, refer to the post-installation steps for Linux. You can also install Docker without root privileges, or configured to run in rootless mode. For instructions on running Docker in rootless mode, refer to run the Docker daemon as a non-root user (rootless mode).
Install pre-releases
Docker also provides a convenience script at https://test.docker.com/ to install pre-releases of Docker on Linux. This script is equal to the script at get.docker.com , but configures your package manager to use the test channel of the Docker package repository. The test channel includes both stable and pre-releases (beta versions, release-candidates) of Docker. Use this script to get early access to new releases, and to evaluate them in a testing environment before they’re released as stable.
To install the latest version of Docker on Linux from the test channel, run:
Upgrade Docker after using the convenience script
If you installed Docker using the convenience script, you should upgrade Docker using your package manager directly. There’s no advantage to re-running the convenience script. Re-running it can cause issues if it attempts to re-install repositories which already exist on the host machine.
Uninstall Docker Engine
Uninstall the Docker Engine, CLI, containerd, and Docker Compose packages:
Images, containers, volumes, or custom configuration files on your host aren’t automatically removed. To delete all images, containers, and volumes:
Установка Docker CE в Ubuntu 18.04
В стандартных репозиториях ОС Ubuntu уже присутствует пакет для Docker, однако, обычно, это не то, что требуется разработчикам, поскольку эти версии считаются устаревшими.
Правильный подход — установить пакет Docker Community Edition (CE) из официального репозитория Docker, что бы и рассмотрим далее.
Сначала вам необходимо удалить все старые пакеты, которые у вас могут быть установлены:
Поскольку мы рассматриваем установку бесплатной версии Docker, то мы будем устанавливать Docker CE, который в официальном репозитории поставщика называется docker-ce.
Docker CE официально поддерживает следующие драйверы хранилищ образов и томов в Ubuntu Linux: Overlay2, aufs, btrfs. По умолчанию, будет использоваться драйвер Overlay2, поскольку он обеспечивает высокую производительность.
Самый простой и удобный способ установки Docker CE — подключение репозиториев Docker и установка с помощью Apt.
Установка из репозитория
Для установки из репозитория необходимо подключить репозиторий Docker к вашему Apt:
Убедитесь, что отпечаток ключа репозитория правильный с помощью поиска:
Добавим репозиторий в Apt:
Теперь можно установить все пакеты, которые требуются для работы Docker:
Проверим работоспособность установленного Docker:
Обновление Docker
Для обновления достаточно воспользоваться этой же инструкцией после выполнения apt-get update:
Установка автоматическим скриптом
Существует способ, который позволяет установить Docker CE с помощью выполнения всего пары команд. Этот способ не рекомендуется использовать при настройке продуктовой среды.
Выполнение команд Docker от непривилегированного пользователя
После выполнения предыдущих действий вы сможете использовать команду docker только через повышение привилегий (sudo) или от пользователя root. Довольно часто это неудобно. Существует простой способ дать непривилегированному пользователю возможность выполнять выполнять команды Docker с помощью добавления пользователя в группу Docker:
Теперь от имени данного пользователя можно выполнить команды Docker без указания sudo:
Этот способ часто применяется как для взаимодействия с Docker в обычной жизни, так и для предоставления доступа к Docker различным приложениям, например, Gitlab runner.
containerd.io vs docker-ce-cli vs docker-ce: what are the differences and what does each package do?
I am trying to install docker on my laptop and I find that there are three packages from the repo:
Can anyone explain to me in simple words what the differences are among these packages, what each one of them does, and what part of the docker architecture each corresponds to? Also, can they work independently on each other?
Based on the instructions at the link below, you need to install all of them. They are probably the runtime, cli tools, and daemon respectively.
containerd.io — daemon to interface with the OS API (in this case, LXC — Linux Containers), essentially decouples Docker from the OS, also provides container services for non-Docker container managers
docker-ce — Docker daemon, this is the part that does all the management work, requires the other two on Linux
docker-ce-cli — CLI tools to control the daemon, you can install them on their own if you want to control a remote Docker daemon
Edit: in a broader sense, containerd can interface with any OS capable of providing the features it requires.