If you are running your Kubernetes cluster on Oracle Container Engine for Kubernetes (commonly known as OKE), then you can have Oracle Cloud Infrastructure automatically provision load balancers for you by creating a Service of type LoadBalancer instead of (or in addition to) installing an ingress controller like Traefik.
OKE Kubernetes worker nodes typically do not have public IP addresses. This means that the NodePort services created by the operator are not usable, because they would expose ports on the worker node’s private IP addresses only, which are not reachable from outside the cluster.
Instead, you can use an Oracle Cloud Infrastructure load balancer to provide access to services running in OKE.
It is also possible, if desirable, to have an Oracle Cloud Infrastructure load balancer route traffic to an ingress controller running inside the Kubernetes cluster and have that ingress controller in turn route traffic to services in the cluster.
When your domain is created by the operator, a number of Kubernetes services are created by the operator, including one for the WebLogic Server Administration Server and one for each Managed Server and cluster.
In the following example, there is a domain called bobs-bookstore in the bob namespace. This domain has a cluster called cluster-1 which exposes traffic on port 31111.
The following Kubernetes YAML file defines a new Service in the same namespace. The selector targets all of the pods in this namespace which are part of the cluster cluster-1, using the annotations that are placed on those pods by the operator. It also defines the port and protocol.
You can include the optional oci-load-balancer-shape annotation (as shown) if you want to specify the shape of the load balancer. Otherwise the default shape (100Mbps) will be used.
apiVersion: v1 kind: Service metadata: name: bobs-bookstore-oci-lb-service namespace: bob annotations: service.beta.kubernetes.io/oci-load-balancer-shape: 400Mbps spec: ports: - name: http port: 31111 protocol: TCP targetPort: 31111 selector: weblogic.clusterName: cluster-1 weblogic.domainUID: bobs-bookstore sessionAffinity: None type: LoadBalancer When you apply this YAML file to your cluster, you will see the new service is created but initially the external IP is shown as <pending>.
$ kubectl -n bob get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE bobs-bookstore-admin-server ClusterIP None <none> 8888/TCP,7001/TCP,30101/TCP 9d bobs-bookstore-admin-server-ext NodePort 10.96.224.13 <none> 7001:32401/TCP 9d bobs-bookstore-cluster-cluster-1 ClusterIP 10.96.86.113 <none> 8888/TCP,8001/TCP,31111/TCP 9d bobs-bookstore-managed-server1 ClusterIP None <none> 8888/TCP,8001/TCP,31111/TCP 9d bobs-bookstore-managed-server2 ClusterIP None <none> 8888/TCP,8001/TCP,31111/TCP 9d bobs-bookstore-oci-lb-service LoadBalancer 10.96.121.216 <pending> 31111:31671/TCP 9s After a short time (typically less than a minute), the Oracle Cloud Infrastructure load balancer will be provisioned and the external IP address will be displayed:
$ kubectl -n bob get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE bobs-bookstore-admin-server ClusterIP None <none> 8888/TCP,7001/TCP,30101/TCP 9d bobs-bookstore-admin-server-ext NodePort 10.96.224.13 <none> 7001:32401/TCP 9d bobs-bookstore-cluster-cluster-1 ClusterIP 10.96.86.113 <none> 8888/TCP,8001/TCP,31111/TCP 9d bobs-bookstore-managed-server1 ClusterIP None <none> 8888/TCP,8001/TCP,31111/TCP 9d bobs-bookstore-managed-server2 ClusterIP None <none> 8888/TCP,8001/TCP,31111/TCP 9d bobs-bookstore-oci-lb-service LoadBalancer 10.96.121.216 132.145.235.215 31111:31671/TCP 55s You can now use the external IP address and port to access your pods. There are several options that can be used to configure more advanced load balancing behavior. For more information, including how to configure SSL support, supporting internal and external subnets, and so one, refer to the Oracle Cloud Infrastructure documentation.