CORD runs on any version of Kubernetes (1.10 or greater), and uses the Helm client-side tool. If you are new to Kubernetes, we recommend https://kubernetes.io/docs/tutorials/ as a good place to start.
Note: We are using a feature in kubernetes 1.10 to allow local persistence of data. This is a beta feature in K8S 1.10.x as of this writing and should be enabled by default. However, if it is not, you will need to enable it as a feature gate when launching kubernetes with the following feature gate settings:
PersistentLocalVolumes=true VolumeScheduling=true MountPropagation=true
More information about feature gates can be found here. More sophisticated use-cases, for example COMAC, require additional settings (see COMAC prerequisites).
Although you are free to set up Kubernetes and Helm in whatever way makes sense for your deployment, the following provides guidelines, pointers, and automated scripts that might be helpful.
The following sections, Single Node Cluster and Multi Node Cluster, offer pointers and scripts to install your favorite version of Kubernetes. Start there, then come back here and follow the steps in the following three subsections.
Once Kubernetes is installed, you should have a KUBECONFIG configuration file containing all the details of your deployment: address of the machine(s), credentials, and so on. The file can be used to access your Kubernetes deployment from any client able to communicate with the Kubernetes installation. To manage the pod, export a KUBECONFIG variable containing the path to the configuration file:
export KUBECONFIG=/path/to/your/kubeconfig/file
You can also permanently export this environment variable, so you don’t have to export it every time you open a new window in your terminal. More info on this topic at https://kubernetes.io/docs/concepts/configuration/organize-cluster-access-kubeconfig/.
In case you have to manage multiple clusters, for example COMAC, extend KUBECONFIG variable to include the configuration file for all clusters.
export KUBECONFIG=/path/to/central/kubeconfig/file:/path/to/edge/kubeconfig/file
After updating KUBECONFIG, you can quickly switch between clusters by using the kubectl config use-context command.
Again assuming Kubernetes is already installed, the next step is to install the CLI tools used to interact with it. kubectl is the basic tool you need. It can be installed on any device able to reach the Kubernetes just installed (i.e., the development laptop, another server, the same machine where Kubernetes is installed).
To install kubectl, follow this step-by-step guide: https://kubernetes.io/docs/tasks/tools/install-kubectl/.
To test the kubectl installation run:
kubectl get pods
Kubernetes should reply to the request showing the pods already deployed. If you've just installed Kubernetes, likely you won't see any pod, yet. That's fine, as long as you don't see errors.