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.