Container Registry:Basic operations on Docker

Background information

Before you use Container Registry, you must install Docker. For more information about how to install Docker, see the following topics Install and use Docker on a Linux instance.

docker login

The following section provides an example on how to log on to a Container Registry Enterprise Edition instance that resides in the China (Hangzhou) region.

1. Specify the domain name of the Container Registry Enterprise Edition instance and enter your username and logon password.

   After you log on to the Container Registry Enterprise Edition instance, Login Succeeded is displayed.

   docker login <Name of the Container Registry Enterprise Edition instance>-registry.cn-hangzhou.cr.aliyuncs.com
   Username: ****@test.com
   Password:
   Login Succeeded

   Note

   • You can obtain the domain name of the Container Registry Enterprise Edition instance on the Access Control page.

   • The logon password is the password that you set in the Container Registry console but is not your Alibaba Cloud account password. If you forget the password that you set, you can set an access credential. For more information, see Configure access credentials for a Container Registry Enterprise Edition instance.

2. View the config.json file to confirm your logon information.

   Sample command:

   cat ~/.docker/config.json

   Expected output:

   {
       "auths": {
           "<Name of the Container Registry Enterprise Edition instance>-registry.cn-hangzhou.cr.aliyuncs.com": {
               "auth": "****"
           }
       }
   }        

docker pull

The following sample code provides an example on how to download the <Name of the Container Registry Enterprise Edition instance>-registry.cn-hangzhou.cr.aliyuncs.com/acs/agent:0.8 image.

Sample command:

docker pull <Name of the Container Registry Enterprise Edition instance>-registry.cn-hangzhou.cr.aliyuncs.com/acs/agent:0.8

Expected output:

0.8: Pulling from acs/agent
5a026b6c4964: Already exists
e4b621e8d9cb: Already exists
8bc2fd04bdd4: Pull complete
a977b0087b3e: Pull complete
8f6e00ea13c6: Pull complete
875dd8c9666f: Pull complete
9c07bcabc35d: Pull complete
Digest: sha256:cac848bd31bccf2a041bda7b57e3051341093abde6859df9ee9d332dfec6ddd9
Status: Downloaded newer image for <Name of the Container Registry Enterprise Edition instance>-registry.cn-hangzhou.cr.aliyuncs.com/acs/agent:0.8            

You can run the docker images command to view the pulled images. Check the repository locations and image tags in the command output.

docker images

Expected output:

REPOSITORY                                                     TAG                 IMAGE ID            CREATED             SIZE
<Name of the Container Registry Enterprise Edition instance>-registry.cn-hangzhou.cr.aliyuncs.com/acs/agent   0.8                 b9ba5841bdb0        24 hours ago        42.18 MB            

docker push

After on-premises images are built or packaged, you can push them to a Container Registry Enterprise Edition instance.

The preparation for pushing images is basically the same as that for pulling images. Make sure that you have the permissions on the repository. Otherwise, an error message is returned after you run the following command.

Sample command:

docker push <Name of the Container Registry Enterprise Edition instance>-registry.cn-hangzhou.cr.aliyuncs.com/acs/agent:0.8

Expected output:

The push refers to a repository [<Enterprise Edition instance name>-registry.cn-hangzhou.cr.aliyuncs.com/acs/agent:0.8]
359f80267111: Layer already exists
7e5fa28d90b8: Layer already exists
b20d7f600f63: Layer already exists
4a159b4f8370: Layer already exists
7c3712ebe877: Layer already exists
d91d130a53aa: Layer already exists
fcad8ad5a40f: Layer already exists
unauthorized: authentication required            

Use a RAM user to log on to a Container Registry Enterprise Edition instance

1. Log on to the Container Registry console as a RAM user. On the Access Credential page, set the logon password.

2. Use <RAM user>@<Enterprise alias> as the logon username.

   You can set and view the enterprise alias of an Alibaba Cloud account in the RAM console. If no enterprise alias is available, the enterprise alias is the UID of the Alibaba Cloud account by default.

   Assume that the RAM user is subaccount and the enterprise alias is accoun-alias. The following sample code provides a logon example:

   docker login <Name of the Container Registry Enterprise Edition instance>-registry.cn-hangzhou.cr.aliyuncs.com
   Username: subaccount@account-alias
   Password:
   Login Succeeded