Istio Installer

This image is used by the rancher-istio chart to intall istio with various configurations.

This installer uses shell scripts to run istioctl install, upgrade and uninstall commands.

Architecture

Uses istioctl and nginx to complete install, upgrade and delete comands for the Istio service mesh.

Overview

This image uses a series of bash scripts to execute istioctl binary comands. The istioctl binary is an Istio configuration command line utility for managing your Istio service mesh.

The current implementation of the istioctl upgrade command makes a call to external github to download Istio manifests to complete the upgrade process. This will fail when running in an airgapped enviornment. To temporarily resolve the issue, this image also uses an nginx server to intercept that call and download the necessary manifest from the docker container. The image bundles the Istio manifests for the versions of Istio that are currently released in a rancher-istio chart.

Making Changes

How to upgrade the istio version

In the Dockerfile, change the environmnet variable ENV ISTIO_VERSION to the version of istio that you would like the installer to support.
Add the same version of istio that you used for ENV ISTIO_VERSIONto the istio_version_array in the fetch_istio_releases.sh script ordering from least to greatest. When doing this step, you also want to double check that the version that was previously used for ENV ISTIO_VERSION also exists in the istio_version_array. This step ensures upgrades work in airgapped environments.

In general, the istio_version_array must include all istio versions from the release branches of rancher/charts

Note: The istio_version_array does not include rancher-istio chart version, just the version of istio that is supported by the rancher-istio chart.
Finally, you need to validate that the create_istio_system.sh and the uninstall_istio_system.sh script commands are still valid. This can be done by checking that the istioctl commands have not changed. You should also check the release notes for any significant changes to how istioctl is used. If there were changes to the commands, update the create_istio_system.sh and the uninstall_istio_system.sh scripts accordingly.

Build

The istio-installer image is built using drone when a new tag is created and pushed to repository. See drone.yaml for drone configurations.

When building the image locally, run docker build -t <your_docker_hub_repo>/istio-installer:<tag> .

How to tag

The istio installer uses the following version format for tags: <x.x.x>-rancher<x>

The <x.x.x> should be set to the version of istio the installer is going to be used for. This can be found in the Dockerfile as the value for the ENV ISTIO_VERSION

The rancher<x> is the build number. This number starts at 1 and increases with each re-tag with the same istio version.`

After all of the changes have been merged into the master branch, fetch a fresh copy of the master branch to your local machine. From there, you can run the following commands to tag and push the tag to the repo

git tag <x.x.x>-rancher<x>
git push <istio_installer_remote_branch> <x.x.x>-rancher<x>

Once the tag is pushed to github, drone will build the docker image and push it to the rancher/istio-installer docker hub repository.

An example tag for a new istio version and push may look like this:

git tag 1.9.6-rancher1
git push upstream 1.9.6-rancher1

If you need to re-tag the same version, that may look like this:

git tag 1.9.6-rancher2
git push upstream 1.9.6-rancher2

axeal / istio-installer