Docker pull

From NovaOrdis Knowledge Base
Jump to: navigation, search

External

Internal

Overview

Pull an image or a repository from a registry and place it into the local registry. By default, unless an explicit registry name is specified, the command pulls from Docker Hub. assuming "docker.io" as registry name.

docker pull <name>[:<tag>]

The command pulls each layer separately, and it will only pull the layers that do not exist in the local repository.

The command accepts an image name or a repository name. For more details on the URL semantics see Docker Concepts - URL.

When no explicit tag is specified, "latest" is implied. The following commands are equivalent:

docker pull novaordis/databot
docker pull novaordis/databot:latest

However, the "latest" tag must exist in the repository on the registry being accessed, for the command to work. More details about the "latest" tag here:

The "latest" tag

Example

docker pull registry.access.redhat.com/openshift3/jenkins-2-rhel7
Using default tag: latest
Trying to pull repository registry.access.redhat.com/openshift3/jenkins-2-rhel7 ...
sha256:c2e5ffc909fc598628caebe56571849cbcbeea6c99f885a9870cb8c5967d5111: Pulling from registry.access.redhat.com/openshift3/jenkins-2-rhel7
26e5ed6899db: Already exists
66dbe984a319: Already exists
634b7b97a070: Already exists
Digest: sha256:c2e5ffc909fc598628caebe56571849cbcbeea6c99f885a9870cb8c5967d5111
Status: Image is up to date for registry.access.redhat.com/openshift3/jenkins-2-rhel7:latest

Pull from a Different Registry

By default, docker pull pulls images from Docker Hub, but an image can be pulled form a different registry by specifying the registry path as prefix of the image name.

docker pull registry.access.redhat.com/rhscl/postgresql-95-rhel7