github.com/itscaro/cli@v0.0.0-20190705081621-c9db0fe93829/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 <!-- This file is maintained within the docker/cli GitHub 8 repository at https://github.com/docker/cli/. Make all 9 pull requests against that repo. If you see this file in 10 another repository, consider it read-only there, as it will 11 periodically be overwritten by the definitive file. Pull 12 requests which include edits to this file in other repositories 13 will be rejected. 14 --> 15 16 # pull 17 18 ```markdown 19 Usage: docker pull [OPTIONS] NAME[:TAG|@DIGEST] 20 21 Pull an image or a repository from a registry 22 23 Options: 24 -a, --all-tags Download all tagged images in the repository 25 --disable-content-trust Skip image verification (default true) 26 --help Print usage 27 -q, --quiet Suppress verbose output 28 ``` 29 30 ## Description 31 32 Most of your images will be created on top of a base image from the 33 [Docker Hub](https://hub.docker.com) registry. 34 35 [Docker Hub](https://hub.docker.com) contains many pre-built images that you 36 can `pull` and try without needing to define and configure your own. 37 38 To download a particular image, or set of images (i.e., a repository), 39 use `docker pull`. 40 41 ### Proxy configuration 42 43 If you are behind an HTTP proxy server, for example in corporate settings, 44 before open a connect to registry, you may need to configure the Docker 45 daemon's proxy settings, using the `HTTP_PROXY`, `HTTPS_PROXY`, and `NO_PROXY` 46 environment variables. To set these environment variables on a host using 47 `systemd`, refer to the [control and configure Docker with systemd](https://docs.docker.com/engine/admin/systemd/#http-proxy) 48 for variables configuration. 49 50 ### Concurrent downloads 51 52 By default the Docker daemon will pull three layers of an image at a time. 53 If you are on a low bandwidth connection this may cause timeout issues and you may want to lower 54 this via the `--max-concurrent-downloads` daemon option. See the 55 [daemon documentation](dockerd.md) for more details. 56 57 ## Examples 58 59 ### Pull an image from Docker Hub 60 61 To download a particular image, or set of images (i.e., a repository), use 62 `docker pull`. If no tag is provided, Docker Engine uses the `:latest` tag as a 63 default. This command pulls the `debian:latest` image: 64 65 ```bash 66 $ docker pull debian 67 68 Using default tag: latest 69 latest: Pulling from library/debian 70 fdd5d7827f33: Pull complete 71 a3ed95caeb02: Pull complete 72 Digest: sha256:e7d38b3517548a1c71e41bffe9c8ae6d6d29546ce46bf62159837aad072c90aa 73 Status: Downloaded newer image for debian:latest 74 ``` 75 76 Docker images can consist of multiple layers. In the example above, the image 77 consists of two layers; `fdd5d7827f33` and `a3ed95caeb02`. 78 79 Layers can be reused by images. For example, the `debian:jessie` image shares 80 both layers with `debian:latest`. Pulling the `debian:jessie` image therefore 81 only pulls its metadata, but not its layers, because all layers are already 82 present locally: 83 84 ```bash 85 $ docker pull debian:jessie 86 87 jessie: Pulling from library/debian 88 fdd5d7827f33: Already exists 89 a3ed95caeb02: Already exists 90 Digest: sha256:a9c958be96d7d40df920e7041608f2f017af81800ca5ad23e327bc402626b58e 91 Status: Downloaded newer image for debian:jessie 92 ``` 93 94 To see which images are present locally, use the [`docker images`](images.md) 95 command: 96 97 ```bash 98 $ docker images 99 100 REPOSITORY TAG IMAGE ID CREATED SIZE 101 debian jessie f50f9524513f 5 days ago 125.1 MB 102 debian latest f50f9524513f 5 days ago 125.1 MB 103 ``` 104 105 Docker uses a content-addressable image store, and the image ID is a SHA256 106 digest covering the image's configuration and layers. In the example above, 107 `debian:jessie` and `debian:latest` have the same image ID because they are 108 actually the *same* image tagged with different names. Because they are the 109 same image, their layers are stored only once and do not consume extra disk 110 space. 111 112 For more information about images, layers, and the content-addressable store, 113 refer to [understand images, containers, and storage drivers](https://docs.docker.com/engine/userguide/storagedriver/imagesandcontainers/). 114 115 116 ### Pull an image by digest (immutable identifier) 117 118 So far, you've pulled images by their name (and "tag"). Using names and tags is 119 a convenient way to work with images. When using tags, you can `docker pull` an 120 image again to make sure you have the most up-to-date version of that image. 121 For example, `docker pull ubuntu:14.04` pulls the latest version of the Ubuntu 122 14.04 image. 123 124 In some cases you don't want images to be updated to newer versions, but prefer 125 to use a fixed version of an image. Docker enables you to pull an image by its 126 *digest*. When pulling an image by digest, you specify *exactly* which version 127 of an image to pull. Doing so, allows you to "pin" an image to that version, 128 and guarantee that the image you're using is always the same. 129 130 To know the digest of an image, pull the image first. Let's pull the latest 131 `ubuntu:14.04` image from Docker Hub: 132 133 ```bash 134 $ docker pull ubuntu:14.04 135 136 14.04: Pulling from library/ubuntu 137 5a132a7e7af1: Pull complete 138 fd2731e4c50c: Pull complete 139 28a2f68d1120: Pull complete 140 a3ed95caeb02: Pull complete 141 Digest: sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2 142 Status: Downloaded newer image for ubuntu:14.04 143 ``` 144 145 Docker prints the digest of the image after the pull has finished. In the example 146 above, the digest of the image is: 147 148 sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2 149 150 Docker also prints the digest of an image when *pushing* to a registry. This 151 may be useful if you want to pin to a version of the image you just pushed. 152 153 A digest takes the place of the tag when pulling an image, for example, to 154 pull the above image by digest, run the following command: 155 156 ```bash 157 $ docker pull ubuntu@sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2 158 159 sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2: Pulling from library/ubuntu 160 5a132a7e7af1: Already exists 161 fd2731e4c50c: Already exists 162 28a2f68d1120: Already exists 163 a3ed95caeb02: Already exists 164 Digest: sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2 165 Status: Downloaded newer image for ubuntu@sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2 166 ``` 167 168 Digest can also be used in the `FROM` of a Dockerfile, for example: 169 170 ```Dockerfile 171 FROM ubuntu@sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2 172 MAINTAINER some maintainer <maintainer@example.com> 173 ``` 174 175 > **Note**: Using this feature "pins" an image to a specific version in time. 176 > Docker will therefore not pull updated versions of an image, which may include 177 > security updates. If you want to pull an updated image, you need to change the 178 > digest accordingly. 179 180 181 ### Pull from a different registry 182 183 By default, `docker pull` pulls images from [Docker Hub](https://hub.docker.com). It is also possible to 184 manually specify the path of a registry to pull from. For example, if you have 185 set up a local registry, you can specify its path to pull from it. A registry 186 path is similar to a URL, but does not contain a protocol specifier (`https://`). 187 188 The following command pulls the `testing/test-image` image from a local registry 189 listening on port 5000 (`myregistry.local:5000`): 190 191 ```bash 192 $ docker pull myregistry.local:5000/testing/test-image 193 ``` 194 195 Registry credentials are managed by [docker login](login.md). 196 197 Docker uses the `https://` protocol to communicate with a registry, unless the 198 registry is allowed to be accessed over an insecure connection. Refer to the 199 [insecure registries](dockerd.md#insecure-registries) section for more information. 200 201 202 ### Pull a repository with multiple images 203 204 By default, `docker pull` pulls a *single* image from the registry. A repository 205 can contain multiple images. To pull all images from a repository, provide the 206 `-a` (or `--all-tags`) option when using `docker pull`. 207 208 This command pulls all images from the `fedora` repository: 209 210 ```bash 211 $ docker pull --all-tags fedora 212 213 Pulling repository fedora 214 ad57ef8d78d7: Download complete 215 105182bb5e8b: Download complete 216 511136ea3c5a: Download complete 217 73bd853d2ea5: Download complete 218 .... 219 220 Status: Downloaded newer image for fedora 221 ``` 222 223 After the pull has completed use the `docker images` command to see the 224 images that were pulled. The example below shows all the `fedora` images 225 that are present locally: 226 227 ```bash 228 $ docker images fedora 229 230 REPOSITORY TAG IMAGE ID CREATED SIZE 231 fedora rawhide ad57ef8d78d7 5 days ago 359.3 MB 232 fedora 20 105182bb5e8b 5 days ago 372.7 MB 233 fedora heisenbug 105182bb5e8b 5 days ago 372.7 MB 234 fedora latest 105182bb5e8b 5 days ago 372.7 MB 235 ``` 236 237 ### Cancel a pull 238 239 Killing the `docker pull` process, for example by pressing `CTRL-c` while it is 240 running in a terminal, will terminate the pull operation. 241 242 ```bash 243 $ docker pull fedora 244 245 Using default tag: latest 246 latest: Pulling from library/fedora 247 a3ed95caeb02: Pulling fs layer 248 236608c7b546: Pulling fs layer 249 ^C 250 ``` 251 252 > **Note**: Technically, the Engine terminates a pull operation when the 253 > connection between the Docker Engine daemon and the Docker Engine client 254 > initiating the pull is lost. If the connection with the Engine daemon is 255 > lost for other reasons than a manual interaction, the pull is also aborted.