/multicluster-controlplane

A standalone controlplane to run ocm core.

Primary LanguageGoApache License 2.0Apache-2.0

Get started

Build

Build binary

make vendor
make build

Build image

export IMAGE_NAME=<customized image. default is quay.io/open-cluster-management/multicluster-controlplane:latest>
make image

Run controlplane as a local binary

export CONFIG_DIR=<the directory of the controlplane configuration file. default is ./_output/controlplane>
make run

You can customize the controlplane configurations by creating a config file and using the environment variable CONFIG_DIR to specify your config file directory.

NOTE: the controlplane config file name must be ocmconfig.yaml

Here is a sample file of ocmconfig.yaml:

dataDirectory: "/.ocm"
apiserver:
  externalHostname: "http://abcdefg.com"
  port: 9443
  caFile: "ca.crt"
  caKeyFile: "ca.key"
etcd:
  mode: external
  prefix: "/registry"
  servers:
  - http://etcd-1:2379
  - http://etcd-2:2379
  caFile: "etcd-trusted-ca.crt"
  certFile: "etcd-client.crt"
  keyFile: "etcd-client.key"

The yaml content shown above is a config file with all fields filled in. Following this to better understand the config file.

Field dataDirectory is a string variable indicating the directory to store generated certs ,embed etcd data and kubeconfig, etc. While this field is missed in the config file, the default value /.ocm makes sense.

Field apiserver contains config for the controlplane apiserver:

  • externalHostname is a string variable indicating the hostname for external access.
  • port is a integer variable indicating the binding port of multicluster controlplane apiserver. The default value is 9443.
  • caFile is a string variable indicating the CA file provided by user to sign all the serving/client certificates.
  • caKeyFile is a string variable indicating the CA Key file for caFile.

Field etcd contains config for the controlplane etcd:

  • mode should be embed or external indicating the multicluster controlplane etcd deploy mode. The value would be embed if field mode is missed.
  • prefix is a string variable indicating controlplane data prefix in etcd. The default value is "/registry".
  • servers is a string array indicating etcd endpoints. The default value is []string{"http://127.0.0.1:2379"}.
  • caFile is a string variable indicating an etcd trusted ca file.
  • certFile is a string variable indicating a client cert file signed by caFile.
  • keyFile is a string variable indicating client key file for certFile.

NOTE: For apiserver field: If you want to use your own CA pair to sign the certificates, the caFile and caKeyFile should be set together. Which means that if one of the two fields is missed/empty, the controlplane would self-generate CA pair to sign the necessary certificates.

Use helm to deploy controlplane in a cluster

  1. Set the environment variable KUBECONFIG to your cluster kubeconfig path
export KUBECONFIG=<the kubeconfig path of your cluster>
  1. (Optional) By default, the controlplane will have an embedded etcd, you can use the following command to deploy an external etcd
make deploy-etcd

This external etcd will be deployed in the namespace multicluster-controlplane-etcd, its certificates will be created at ./_output/etcd/deploy/cert-etcd and its service urls will be: http://etcd-0.etcd.multicluster-controlplane-etcd:2379, http://etcd-1.etcd.multicluster-controlplane-etcd:2379, and http://etcd-2.etcd.multicluster-controlplane-etcd:2379

  1. Run following command to deploy a controlplane
helm repo add ocm https://openclustermanagement.blob.core.windows.net/releases/
helm repo update
helm search repo ocm
helm install -n multicluster-controlplane multicluster-controlplane ocm/multicluster-controlplane --create-namespace --set <values to set>
  • To provide your own ca pairs for controlplane with the following arguements:

    --set-file apiserver.ca="<path-to-ca>",apiserver.cakey="<path-to-ca-key>"
  • To use external etcd with the following arguements:

    --set-file etcd.ca="<path-to-etcd-ca>",etcd.cert="<path-to-etcd-client-cert>",etcd.certkey="<path-to-etcd-client-cert-key>"
    --set etcd.mode="external",etcd.servers={server1, server2, ...}
  • To use the OpenShift route with the following arguements:

    --set route.enabled=true
  • To use the load balance service with the following arguements:

    --set loadbalancer.enabled=true
  • To use the node port serive with the following arguements:

    --set nodeport.enabled=true
    --set nodeport.port=<your-node-port>
  • To enable the self management with the following arguements:

    --set enableSelfManagement=true
  • To delegate the authentication with kube-apiserver with the following arguements:

    --set enableDelegatingAuthentication=true

More available config values can be found from here.

Uninstall the controlplane

helm uninstall -n multicluster-controlplane multicluster-controlplane

Access the controlplane

  • If you run the controlplane as a binary, the controlplane kubeconfig file is in _output/controlplane/.ocm/cert/kube-aggregator.kubeconfig

  • If you deploy the controlplane in a cluster, run the following command to get the controlplane kubeconfig

    kubectl -n multicluster-controlplane get secrets multicluster-controlplane-kubeconfig -ojsonpath='{.data.kubeconfig}' | base64 -d > multicluster-controlplane.kubeconfig

    If you enable the authentication delegating, you can set a context for your controlplane in your cluster kubeconfig with the following commands

    external_host_name=<your controplane external host name>
    # if you want to add the ca of your cluster kube-apiserver, using the command:
    # kubectl config set-cluster multicluster-controlplane --server="https://${external_host_name}" --embed-certs --certificate-authority=<the ca path of your cluster kube-apiserver>
    kubectl config set-cluster multicluster-controlplane --server="https://${external_host_name}" --insecure-skip-tls-verify
    kubectl config set-context multicluster-controlplane --cluster=multicluster-controlplane --user=kube:admin --namespace=default

Join a cluster

You can use clusteradm to access and join a cluster.

clusteradm --kubeconfig=<controlplane kubeconfig file> get token --use-bootstrap-token
clusteradm join --hub-token <controlplane token> --hub-apiserver <controlplane apiserver> --cluster-name <cluster name>
clusteradm --kubeconfig=<controlplane kubeconfig file> accept --clusters <cluster name>

Note: clusteradm version should be v0.4.1 or later