Continuous Delivery with Docker and Jenkins

Tagging images

Images can be tagged. We've already done this while creating our own images, for example, in the case of building the hello-world_python image:

$ docker build -t hello-world_python .

The -t flag describes the tag of the image. If we didn't use it, then the image would be built without any tags and, as a result, we would have to address it by its ID (hash) in order to run the container.

The image can have multiple tags, and they should follow the naming convention:

<registry_address>/<image_name>:<version>

The tag consists of the following parts:

• registry_address: IP and port of the registry or the alias name
• image_name: name of the image that is built, for example, ubuntu
• version: a version of the image in any form, for example, ...