skopeo:tldr:3485b

The command you mentioned is used to copy Docker images from a source registry to a destination registry. Here's an explanation of the different parts of the command:

1. skopeo: It is a command-line tool used for various operations on container images, including copying, inspecting, and deleting images.

2. copy: This is a subcommand in skopeo used to copy images between different registries.

3. docker://${source_registry}/${image:tag}: This represents the source image's location in a Docker-compatible registry. Let's break it down:

   • docker://: Indicates that the registry uses the Docker V2 API.
   • ${source_registry}: The URL or hostname of the registry where the source image is located.
   • ${image:tag}: The name and tag of the image you want to copy from the source registry.

4. docker://${destination_registry}/${image:tag}: This represents the destination image's location in another Docker-compatible registry. It has a similar structure to the source image's location, with the following changes:

   • ${destination_registry}: The URL or hostname of the registry where you want to copy the image.
   • ${image:tag}: The name and tag of the image you want to assign in the destination registry.

So, when you run this command, skopeo will copy the specified Docker image (identified by ${image:tag}) from the source registry to the destination registry.