tkgguestconfig

Application for updating TKG Guest Clusters and Nodes on vSphere 7 with Tanzu

Purpose

The purpose of this project is to provide a mechanism to update Tanzu Kubernetes Grid child clusters on VMware vSphere 7 with Tanzu.

TKG guest clusters often need special configurations updated to successfully integrate into an environment. Configuring trusted certificates, etc.

For more details about how and why this is necessary visit: theITHollow.com

How

This project uses two containers.

1. vLogins - This container is used as an init container that will login to a vSphere Kubernetes supervisor namespace and create a KUBECONFIG file. This file will be placed in a volume under /tkgconfigs/kubeconfig and can be used for future commands.

2. ClusterConfig - This container uses the KUBECONFIG file to perform additional operations. The script within could be used to copy files over, restart services, reconfigure settings, etc.

Instructions

1. Obtain the latest version of the linux kubectl-vsphere plugin from your Supervisor cluster and place it in the vlogins folder. There is a .md file in that directory as a placeholder. That file can be deleted when you've copied over the kubectl-vsphere plugin binary. Be sure you grab the Linux version.

2. Write your custom code. The clusterconfig/clusterconfig.sh script is what executes commands on the guest cluster. There are example configs in there already, but you should update the section labeled: #### YOUR CODE GOES IN THE SECTION BELOW!!! with your own code to perform whatever configurations you need on those nodes.

3. Update the docker-compose.yml file with the image registry being used to store repos. You can do this by replacing the IMAGE_REGISTRY_GOES_HERE variable with your repo.

4. Build the docker images using the docker-compose.yml file by running:

docker compose build && docker compose push

The previous command will build both containers and push them to the image registry you specified in step 2.

5. Update the tkgconfig.yaml file with the appropriate images. You can do this by replacing the IMAGE_REGISTRY_GOES_HERE placeholder with your own image registry. It should match the image registry used in step 2.

6. Update the deployment variable in the tkgconfig.yaml file to match your environment.

-- Arguments

-n: Supervisor Namespace where the guest cluster lives
-u: username for logging in
-p: password for logging in
-s: supervisor API Endpoint (What you'd use with the `kubectl vsphere login command after the `--server=` switch)
-g: guest cluster name

7. Deploy the tkgconfig.yaml manifest to a supervisor cluster's namespace where the guest cluster lives.

8. After the container is successfully deployed, it should perform the login, run the custom scripts and then sleep. You can delete the pod after this, automate the deletion, or keep it around for bastion pod. Note: the login is only good for 10 hours before the token expires.