Kubernetes Resources in an IOC Instance#
Learning about Helm and Kubernetes Manifests#
It is instructive to see what helm is doing when you deploy an IOC.
Helm uses templates to generate a Kubernetes Manifest which defines a set of resources. It applies this manifest to the cluster using kubectl.
To inspect the kubernetes manifest YAML that is created when we deploy the example IOC you can use the following command from inside of your example beamline repository:
ec template services/bl01t-ea-ioc-01
This is expanding the local helm chart in the services/bl01t-ea-ioc-01 folder and using
its config/ioc.yaml plus the templates in helm-ioc-lib. These templates
are expanded using the values in the services/bl01t-ea-ioc-01/values.yaml file and also
helm/shared/values.yaml and finally the default values.yaml file
from the helm-ioc-lib.
For a description of the key resources we create in this Kubernetes manifest see the next heading.
Kubernetes Resources in an IOC Instance#
TODO - This is a work in progress.
The key resources that we are asking Kubernetes to create are:
Deployment. Tells Kubernetes to run one and only one Generic IOC container. See deployments:https://kubernetes.io/docs/concepts/workloads/controllers/deployment/