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docker pull


Pull an image or a repository from a registry

Usage

$ docker pull [OPTIONS] NAME[:TAG|@DIGEST]
+

Refer to the options section for an overview of available OPTIONS for this command.

Description

Most of your images will be created on top of a base image from the Docker Hub registry.

Docker Hub contains many pre-built images that you can pull and try without needing to define and configure your own.

To download a particular image, or set of images (i.e., a repository), use docker pull.

Proxy configuration

If you are behind an HTTP proxy server, for example in corporate settings, before open a connect to registry, you may need to configure the Docker daemon’s proxy settings, using the HTTP_PROXY, HTTPS_PROXY, and NO_PROXY environment variables. To set these environment variables on a host using systemd, refer to the control and configure Docker with systemd for variables configuration.

Concurrent downloads

By default the Docker daemon will pull three layers of an image at a time. If you are on a low bandwidth connection this may cause timeout issues and you may want to lower this via the --max-concurrent-downloads daemon option. See the daemon documentation for more details.

For example uses of this command, refer to the examples section below.

Options

Name, shorthand Default Description
+--all-tags , -a + Download all tagged images in the repository
--disable-content-trust true Skip image verification
--platform Set platform if server is multi-platform capable
+--quiet , -q + Suppress verbose output

Examples

Pull an image from Docker Hub

To download a particular image, or set of images (i.e., a repository), use docker pull. If no tag is provided, Docker Engine uses the :latest tag as a default. This command pulls the debian:latest image:

$ docker pull debian
+
+Using default tag: latest
+latest: Pulling from library/debian
+fdd5d7827f33: Pull complete
+a3ed95caeb02: Pull complete
+Digest: sha256:e7d38b3517548a1c71e41bffe9c8ae6d6d29546ce46bf62159837aad072c90aa
+Status: Downloaded newer image for debian:latest
+

Docker images can consist of multiple layers. In the example above, the image consists of two layers; fdd5d7827f33 and a3ed95caeb02.

Layers can be reused by images. For example, the debian:jessie image shares both layers with debian:latest. Pulling the debian:jessie image therefore only pulls its metadata, but not its layers, because all layers are already present locally:

$ docker pull debian:jessie
+
+jessie: Pulling from library/debian
+fdd5d7827f33: Already exists
+a3ed95caeb02: Already exists
+Digest: sha256:a9c958be96d7d40df920e7041608f2f017af81800ca5ad23e327bc402626b58e
+Status: Downloaded newer image for debian:jessie
+

To see which images are present locally, use the docker images command:

$ docker images
+
+REPOSITORY   TAG      IMAGE ID        CREATED      SIZE
+debian       jessie   f50f9524513f    5 days ago   125.1 MB
+debian       latest   f50f9524513f    5 days ago   125.1 MB
+

Docker uses a content-addressable image store, and the image ID is a SHA256 digest covering the image’s configuration and layers. In the example above, debian:jessie and debian:latest have the same image ID because they are actually the same image tagged with different names. Because they are the same image, their layers are stored only once and do not consume extra disk space.

For more information about images, layers, and the content-addressable store, refer to understand images, containers, and storage drivers.

Pull an image by digest (immutable identifier)

So far, you’ve pulled images by their name (and “tag”). Using names and tags is a convenient way to work with images. When using tags, you can docker pull an image again to make sure you have the most up-to-date version of that image. For example, docker pull ubuntu:20.04 pulls the latest version of the Ubuntu 20.04 image.

In some cases you don’t want images to be updated to newer versions, but prefer to use a fixed version of an image. Docker enables you to pull an image by its digest. When pulling an image by digest, you specify exactly which version of an image to pull. Doing so, allows you to “pin” an image to that version, and guarantee that the image you’re using is always the same.

To know the digest of an image, pull the image first. Let’s pull the latest ubuntu:20.04 image from Docker Hub:

$ docker pull ubuntu:20.04
+
+20.04: Pulling from library/ubuntu
+16ec32c2132b: Pull complete
+Digest: sha256:82becede498899ec668628e7cb0ad87b6e1c371cb8a1e597d83a47fac21d6af3
+Status: Downloaded newer image for ubuntu:20.04
+docker.io/library/ubuntu:20.04
+

Docker prints the digest of the image after the pull has finished. In the example above, the digest of the image is:

sha256:82becede498899ec668628e7cb0ad87b6e1c371cb8a1e597d83a47fac21d6af3
+

Docker also prints the digest of an image when pushing to a registry. This may be useful if you want to pin to a version of the image you just pushed.

A digest takes the place of the tag when pulling an image, for example, to pull the above image by digest, run the following command:

$ docker pull ubuntu@sha256:82becede498899ec668628e7cb0ad87b6e1c371cb8a1e597d83a47fac21d6af3
+
+docker.io/library/ubuntu@sha256:82becede498899ec668628e7cb0ad87b6e1c371cb8a1e597d83a47fac21d6af3: Pulling from library/ubuntu
+Digest: sha256:82becede498899ec668628e7cb0ad87b6e1c371cb8a1e597d83a47fac21d6af3
+Status: Image is up to date for ubuntu@sha256:82becede498899ec668628e7cb0ad87b6e1c371cb8a1e597d83a47fac21d6af3
+docker.io/library/ubuntu@sha256:82becede498899ec668628e7cb0ad87b6e1c371cb8a1e597d83a47fac21d6af3
+

Digest can also be used in the FROM of a Dockerfile, for example:

FROM ubuntu@sha256:82becede498899ec668628e7cb0ad87b6e1c371cb8a1e597d83a47fac21d6af3
+LABEL org.opencontainers.image.authors="some maintainer <maintainer@example.com>"
+

Note

Using this feature “pins” an image to a specific version in time. Docker will therefore not pull updated versions of an image, which may include security updates. If you want to pull an updated image, you need to change the digest accordingly.

Pull from a different registry

By default, docker pull pulls images from Docker Hub. It is also possible to manually specify the path of a registry to pull from. For example, if you have set up a local registry, you can specify its path to pull from it. A registry path is similar to a URL, but does not contain a protocol specifier (https://).

The following command pulls the testing/test-image image from a local registry listening on port 5000 (myregistry.local:5000):

$ docker pull myregistry.local:5000/testing/test-image
+

Registry credentials are managed by docker login.

Docker uses the https:// protocol to communicate with a registry, unless the registry is allowed to be accessed over an insecure connection. Refer to the insecure registries section for more information.

Pull a repository with multiple images

By default, docker pull pulls a single image from the registry. A repository can contain multiple images. To pull all images from a repository, provide the -a (or --all-tags) option when using docker pull.

This command pulls all images from the fedora repository:

$ docker pull --all-tags fedora
+
+Pulling repository fedora
+ad57ef8d78d7: Download complete
+105182bb5e8b: Download complete
+511136ea3c5a: Download complete
+73bd853d2ea5: Download complete
+....
+
+Status: Downloaded newer image for fedora
+

After the pull has completed use the docker images command to see the images that were pulled. The example below shows all the fedora images that are present locally:

$ docker images fedora
+
+REPOSITORY   TAG         IMAGE ID        CREATED      SIZE
+fedora       rawhide     ad57ef8d78d7    5 days ago   359.3 MB
+fedora       20          105182bb5e8b    5 days ago   372.7 MB
+fedora       heisenbug   105182bb5e8b    5 days ago   372.7 MB
+fedora       latest      105182bb5e8b    5 days ago   372.7 MB
+

Cancel a pull

Killing the docker pull process, for example by pressing CTRL-c while it is running in a terminal, will terminate the pull operation.

$ docker pull fedora
+
+Using default tag: latest
+latest: Pulling from library/fedora
+a3ed95caeb02: Pulling fs layer
+236608c7b546: Pulling fs layer
+^C
+

Note

The Engine terminates a pull operation when the connection between the Docker Engine daemon and the Docker Engine client initiating the pull is lost. If the connection with the Engine daemon is lost for other reasons than a manual interaction, the pull is also aborted.

+

+ © 2019 Docker, Inc.
Licensed under the Apache License, Version 2.0.
Docker and the Docker logo are trademarks or registered trademarks of Docker, Inc. in the United States and/or other countries.
Docker, Inc. and other parties may also have trademark rights in other terms used herein.
+ https://docs.docker.com/engine/reference/commandline/pull/ +

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