Helm Reference

Helm is the package manager for Kubernetes. It lets you define, install, and upgrade Kubernetes base applications. For more information about Helm, please the visit official website: https://helm.sh.

For information on how to install helm please refer to Installing Helm.

CORD Helm Charts

All helm charts used to install CORD can be found in the helm-chart repository. Most of the top-level directories in that repository (e.g., onos, voltha, xos-core) correspond to components of CORD that can be installed independently. For example, it is possible to bring up onos without voltha, and vice versa. You can also bring up XOS by itself (xos-core) or XOS with its GUI (xos-core and xos-gui). This can be useful if you want to work on just the CORD data models, without any backend components.

The xos-services and xos-profiles directories contain helm charts for individual services and profiles (a mesh of services), respectively. While it is possible to use Helm to bring up an individual service, collections of related services are typically installed as a unit; we call this unit a profile. Looking in the xos-profiles directory, rcord-lite is an example profile. It corresponds to R-CORD, and inspecting its requirements.yaml file shows that it, in turn, depends on the volt and vrouter services, among several others.

Some of the profiles bring up sub-systems that other profiles then build upon. For example, base-openstack brings up three platform related services (onos-service, openstack, and vtn-service), which effectively provisions CORD to support OpenStack-based VNFs. Once the services in the base-openstack profile are running, it is then possible to bring up the mcord profile, which corresponds to ~10 other services. It is also possible to bring up an individual service by executing its helm chart; for example xos-services/simpleexampleservice.

Note: Sometimes we install Individual services by first "wrapping" them in a profile. For example, SimpleExampleService is deployed from the xos-profiles/demo-simpleexampleservice profile, rather than directly from xos-services/simpleexampleservice. The latter is included by reference from the former. This is not a fundamental limitation, but we do it when we want to run the tosca-loader that loads a TOSCA workflow into CORD. This feature is currently available at only the profile level.

Similarly, the base-kubernetes profile brings up Kubernetes in support of container-based VNFs. This corresponds to the kubernetes-service, not to be confused with CORD's use of Kubernetes to deploy the CORD control plane. Once this profile is running, it is possible to bring up an example VNF in a container by executing its helm chart; for example xos-profiles/demo-simpleexampleservice.

Note: The base-kubernetes configuration does not yet incorporate VTN. Doing so is work-in-progress.

Finally, note that the templates sub-directory in both the xos-services and xos-profiles directories includes one or more TOSCA-related files. These play a role in configuring the service graph and provisioning the individual services contained in that service graph. This happens once the helm charts have done their job, and is technically a post-install operation, as discussed in the Operations Guide.

Download the helm-charts Repository

You can get the CORD helm charts by cloning the helm-charts repository:

git clone https://gerrit.opencord.org/helm-charts -b cord-6.0

Note: If you have downloaded the CORD code following the Getting the Source Code guide, you'll find it in ~/cord/helm-charts.

IMPORTANT: All the helm commands needs to be executed from within this directory

Add the CORD Repository to Helm

If you don't want to download the repository, you can just add the OPENCord charts to your helm repo:

helm repo add cord https://charts.opencord.org/master
helm repo update

If you decide to follow this route, the cord/ prefix needs to be added to specify the repo to use. For example:

helm install -n xos-core xos-core

will become

helm install -n xos-core cord/xos-core

CORD Example Values

There is an example directory in the helm-chart repository. The files contained in that directory are examples of possible overrides to obtain a custom deployment.

For example, it is possible to deploy a single instance of kafka, for development purposes, by using this value file:

helm install --name cord-kafka incubator/kafka -f examples/kafka-single.yaml