github.com/pwn-term/docker@v0.0.0-20210616085119-6e977cce2565/cli/docs/reference/commandline/pull.md (about)

     1  ---
     2  title: "pull"
     3  description: "The pull command description and usage"
     4  keywords: "pull, image, hub, docker"
     5  ---
     6  
     7  # pull
     8  
     9  ```markdown
    10  Usage:  docker pull [OPTIONS] NAME[:TAG|@DIGEST]
    11  
    12  Pull an image or a repository from a registry
    13  
    14  Options:
    15    -a, --all-tags                Download all tagged images in the repository
    16        --disable-content-trust   Skip image verification (default true)
    17        --help                    Print usage
    18    -q, --quiet                   Suppress verbose output
    19  ```
    20  
    21  ## Description
    22  
    23  Most of your images will be created on top of a base image from the
    24  [Docker Hub](https://hub.docker.com) registry.
    25  
    26  [Docker Hub](https://hub.docker.com) contains many pre-built images that you
    27  can `pull` and try without needing to define and configure your own.
    28  
    29  To download a particular image, or set of images (i.e., a repository),
    30  use `docker pull`.
    31  
    32  ### Proxy configuration
    33  
    34  If you are behind an HTTP proxy server, for example in corporate settings,
    35  before open a connect to registry, you may need to configure the Docker
    36  daemon's proxy settings, using the `HTTP_PROXY`, `HTTPS_PROXY`, and `NO_PROXY`
    37  environment variables. To set these environment variables on a host using
    38  `systemd`, refer to the [control and configure Docker with systemd](https://docs.docker.com/config/daemon/systemd/#httphttps-proxy)
    39  for variables configuration.
    40  
    41  ### Concurrent downloads
    42  
    43  By default the Docker daemon will pull three layers of an image at a time.
    44  If you are on a low bandwidth connection this may cause timeout issues and you may want to lower
    45  this via the `--max-concurrent-downloads` daemon option. See the
    46  [daemon documentation](dockerd.md) for more details.
    47  
    48  ## Examples
    49  
    50  ### Pull an image from Docker Hub
    51  
    52  To download a particular image, or set of images (i.e., a repository), use
    53  `docker pull`. If no tag is provided, Docker Engine uses the `:latest` tag as a
    54  default. This command pulls the `debian:latest` image:
    55  
    56  ```bash
    57  $ docker pull debian
    58  
    59  Using default tag: latest
    60  latest: Pulling from library/debian
    61  fdd5d7827f33: Pull complete
    62  a3ed95caeb02: Pull complete
    63  Digest: sha256:e7d38b3517548a1c71e41bffe9c8ae6d6d29546ce46bf62159837aad072c90aa
    64  Status: Downloaded newer image for debian:latest
    65  ```
    66  
    67  Docker images can consist of multiple layers. In the example above, the image
    68  consists of two layers; `fdd5d7827f33` and `a3ed95caeb02`.
    69  
    70  Layers can be reused by images. For example, the `debian:jessie` image shares
    71  both layers with `debian:latest`. Pulling the `debian:jessie` image therefore
    72  only pulls its metadata, but not its layers, because all layers are already
    73  present locally:
    74  
    75  ```bash
    76  $ docker pull debian:jessie
    77  
    78  jessie: Pulling from library/debian
    79  fdd5d7827f33: Already exists
    80  a3ed95caeb02: Already exists
    81  Digest: sha256:a9c958be96d7d40df920e7041608f2f017af81800ca5ad23e327bc402626b58e
    82  Status: Downloaded newer image for debian:jessie
    83  ```
    84  
    85  To see which images are present locally, use the [`docker images`](images.md)
    86  command:
    87  
    88  ```bash
    89  $ docker images
    90  
    91  REPOSITORY   TAG      IMAGE ID        CREATED      SIZE
    92  debian       jessie   f50f9524513f    5 days ago   125.1 MB
    93  debian       latest   f50f9524513f    5 days ago   125.1 MB
    94  ```
    95  
    96  Docker uses a content-addressable image store, and the image ID is a SHA256
    97  digest covering the image's configuration and layers. In the example above,
    98  `debian:jessie` and `debian:latest` have the same image ID because they are
    99  actually the *same* image tagged with different names. Because they are the
   100  same image, their layers are stored only once and do not consume extra disk
   101  space.
   102  
   103  For more information about images, layers, and the content-addressable store,
   104  refer to [understand images, containers, and storage drivers](https://docs.docker.com/storage/storagedriver/).
   105  
   106  
   107  ### Pull an image by digest (immutable identifier)
   108  
   109  So far, you've pulled images by their name (and "tag"). Using names and tags is
   110  a convenient way to work with images. When using tags, you can `docker pull` an
   111  image again to make sure you have the most up-to-date version of that image.
   112  For example, `docker pull ubuntu:14.04` pulls the latest version of the Ubuntu
   113  14.04 image.
   114  
   115  In some cases you don't want images to be updated to newer versions, but prefer
   116  to use a fixed version of an image. Docker enables you to pull an image by its
   117  *digest*. When pulling an image by digest, you specify *exactly* which version
   118  of an image to pull. Doing so, allows you to "pin" an image to that version,
   119  and guarantee that the image you're using is always the same.
   120  
   121  To know the digest of an image, pull the image first. Let's pull the latest
   122  `ubuntu:14.04` image from Docker Hub:
   123  
   124  ```bash
   125  $ docker pull ubuntu:14.04
   126  
   127  14.04: Pulling from library/ubuntu
   128  5a132a7e7af1: Pull complete
   129  fd2731e4c50c: Pull complete
   130  28a2f68d1120: Pull complete
   131  a3ed95caeb02: Pull complete
   132  Digest: sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
   133  Status: Downloaded newer image for ubuntu:14.04
   134  ```
   135  
   136  Docker prints the digest of the image after the pull has finished. In the example
   137  above, the digest of the image is:
   138  
   139      sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
   140  
   141  Docker also prints the digest of an image when *pushing* to a registry. This
   142  may be useful if you want to pin to a version of the image you just pushed.
   143  
   144  A digest takes the place of the tag when pulling an image, for example, to
   145  pull the above image by digest, run the following command:
   146  
   147  ```bash
   148  $ docker pull ubuntu@sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
   149  
   150  sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2: Pulling from library/ubuntu
   151  5a132a7e7af1: Already exists
   152  fd2731e4c50c: Already exists
   153  28a2f68d1120: Already exists
   154  a3ed95caeb02: Already exists
   155  Digest: sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
   156  Status: Downloaded newer image for ubuntu@sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
   157  ```
   158  
   159  Digest can also be used in the `FROM` of a Dockerfile, for example:
   160  
   161  ```dockerfile
   162  FROM ubuntu@sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
   163  LABEL maintainer="some maintainer <maintainer@example.com>"
   164  ```
   165  
   166  > **Note**
   167  >
   168  > Using this feature "pins" an image to a specific version in time.
   169  > Docker will therefore not pull updated versions of an image, which may include
   170  > security updates. If you want to pull an updated image, you need to change the
   171  > digest accordingly.
   172  
   173  
   174  ### Pull from a different registry
   175  
   176  By default, `docker pull` pulls images from [Docker Hub](https://hub.docker.com). It is also possible to
   177  manually specify the path of a registry to pull from. For example, if you have
   178  set up a local registry, you can specify its path to pull from it. A registry
   179  path is similar to a URL, but does not contain a protocol specifier (`https://`).
   180  
   181  The following command pulls the `testing/test-image` image from a local registry
   182  listening on port 5000 (`myregistry.local:5000`):
   183  
   184  ```bash
   185  $ docker pull myregistry.local:5000/testing/test-image
   186  ```
   187  
   188  Registry credentials are managed by [docker login](login.md).
   189  
   190  Docker uses the `https://` protocol to communicate with a registry, unless the
   191  registry is allowed to be accessed over an insecure connection. Refer to the
   192  [insecure registries](dockerd.md#insecure-registries) section for more information.
   193  
   194  
   195  ### Pull a repository with multiple images
   196  
   197  By default, `docker pull` pulls a *single* image from the registry. A repository
   198  can contain multiple images. To pull all images from a repository, provide the
   199  `-a` (or `--all-tags`) option when using `docker pull`.
   200  
   201  This command pulls all images from the `fedora` repository:
   202  
   203  ```bash
   204  $ docker pull --all-tags fedora
   205  
   206  Pulling repository fedora
   207  ad57ef8d78d7: Download complete
   208  105182bb5e8b: Download complete
   209  511136ea3c5a: Download complete
   210  73bd853d2ea5: Download complete
   211  ....
   212  
   213  Status: Downloaded newer image for fedora
   214  ```
   215  
   216  After the pull has completed use the `docker images` command to see the
   217  images that were pulled. The example below shows all the `fedora` images
   218  that are present locally:
   219  
   220  ```bash
   221  $ docker images fedora
   222  
   223  REPOSITORY   TAG         IMAGE ID        CREATED      SIZE
   224  fedora       rawhide     ad57ef8d78d7    5 days ago   359.3 MB
   225  fedora       20          105182bb5e8b    5 days ago   372.7 MB
   226  fedora       heisenbug   105182bb5e8b    5 days ago   372.7 MB
   227  fedora       latest      105182bb5e8b    5 days ago   372.7 MB
   228  ```
   229  
   230  ### Cancel a pull
   231  
   232  Killing the `docker pull` process, for example by pressing `CTRL-c` while it is
   233  running in a terminal, will terminate the pull operation.
   234  
   235  ```bash
   236  $ docker pull fedora
   237  
   238  Using default tag: latest
   239  latest: Pulling from library/fedora
   240  a3ed95caeb02: Pulling fs layer
   241  236608c7b546: Pulling fs layer
   242  ^C
   243  ```
   244  
   245  > **Note**
   246  >
   247  > The Engine terminates a pull operation when the connection between the Docker
   248  > Engine daemon and the Docker Engine client initiating the pull is lost. If the
   249  > connection with the Engine daemon is lost for other reasons than a manual
   250  > interaction, the pull is also aborted.