Authenticate with the container registry

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To authenticate with the container registry, you can use a:

All of these authentication methods require the minimum scope:

For read (pull) access, to be read_registry.
For write (push) access, to be write_registry and read_registry.

To authenticate, run the docker login command. For example:

TOKEN=<token>
echo "$TOKEN" | docker login registry.example.com -u <username> --password-stdin

Use GitLab CI/CD to authenticate

To use CI/CD to authenticate with the container registry, you can use:

The CI_REGISTRY_USER CI/CD variable.

This variable holds a per-job user with read-write access to the container registry. Its password is also automatically created and available in CI_REGISTRY_PASSWORD.
```
echo "$CI_REGISTRY_PASSWORD" | docker login $CI_REGISTRY -u $CI_REGISTRY_USER --password-stdin
```

A CI job token.

echo "$CI_JOB_TOKEN" | docker login $CI_REGISTRY -u $CI_REGISTRY_USER --password-stdin

A deploy token with the minimum scope of:
- For read (pull) access, read_registry.
- For write (push) access, read_registry and write_registry.
```
echo "$CI_DEPLOY_PASSWORD" | docker login $CI_REGISTRY -u $CI_DEPLOY_USER --password-stdin
```
A personal access token with the minimum scope of:
- For read (pull) access, read_registry.
- For write (push) access, read_registry and write_registry.
```
echo "<access_token>" | docker login $CI_REGISTRY -u <username> --password-stdin
```