Installing Zowe runtime Docker Image (Technical Preview)

Technical Preview

Docker is a way to create a pre-packaged set of software and configuration called an "Image". Images are used to create Docker "Containers", which run the Image contents in isolation from the other software running on the same system. Docker containers are the runtime environment, and Images are what they are crated from.

The majority of the Zowe server runtime is available in the form of a Docker Image, among other options. To use this image, you must have set up the Zowe server runtime on z/OS, z/OSMF, or both depending on which Zowe components you will use.

If you have not set up the Zowe server runtime on z/OS, please follow the steps found in Docker Installation Roadmap.

This guide assumes you are using Linux or zLinux and have already downloaded Docker itself. If you have not yet done so, please review System Requirements.

Installing via Docker Hub

Zowe's Docker Image is hosted on Docker Hub, which is the default location from which you can use the Docker command line utility to download and update Docker Images. On Docker Hub, the Zowe server runtime image is named ompzowe/server-bundle.

You can download a Docker Image by using the Docker command line utility docker pull imagename where imagename is one of the following:

• The latest version of zowe, ompzowe/server-bundle:latest
• The latest version for the platform you are running on, such as ompzowe/server-bundle:amd64 for Linux
• A specific version by referencing the version's digest, such as ompzowe/server-bundle@sha256:bdbc0617b02e16a452f6d4de50b8b13e56592e309b4c68f9ea52c82303ad57ec

The latest digests can be seen on the image's tags page.

Installing via direct download

You can install a Docker Image that has been downloaded as a .tar archive from anywhere, such as Zowe.org.

Loading an image from .tar file

To install a Docker Image that you have downloaded as a tar file from somewhere, transfer the file to the destination host and then run the following command: docker image load -i path_to_tar

Confirming the installation

The docker images command lists the images a system currently has, which make them available for creating containers from.

# docker imagesREPOSITORY                         TAG                 IMAGE ID            CREATED             SIZEompzowe/server-bundle              amd64               ceb8c50d2381        2 hours ago         1.27GB

Upgrading

Once installed, it is possible to upgrade an image by using docker pull with the same imagename as before, or by using docker image load to load another image of the same type. Newer containers can be created from newer images. In Zowe, configuration can be persisted between containers. More information on this subject can be found in Configuring Docker Container documentation.

When upgrading, it is possible that the previous image may persist. You may see the old image tagged as <none>.

# docker imagesREPOSITORY                         TAG                 IMAGE ID            CREATED             SIZEompzowe/server-bundle              amd64               ceb8c50d2381        2 hours ago         1.27GB<none>                             <none>              1e52fadc2918        2 weeks ago         3.03GB

If you see this and want to clean up the older images to preserve storage space, you can run the command docker rmi IMAGE_ID to remove an image, where IMAGE_ID is the code seen from the images command.

Verifying authenticity using Docker signing

Dockerhub is equiped with an option authenticity verification feature that you can use to ensure that the Zowe release you are pulling from Dockerhub is legitimate.

Note: With this verification turned on, you will not be able to download images that are not signed.

To turn use this feature, you must set the environment variable DOCKER_CONTENT_TRUST=1, then use the "docker pull" command on images that you want to download. This feature can be set to be either temporary or permanent.

Temporary example DOCKER_CONTENT_TRUST=1 docker pull ompzowe/server-bundle:amd64

Permanent example

1. Add export DOCKER_CONTENT_TRUST=1 to your shell profile, such as echo export DOCKER_CONTENT_TRUST=1 >> .profile

2. Login again so that the export can take effect.

3. Use docker commands, such as docker pull ompzowe/server-bundle:amd64