DigitalOcean Kubernetes (DOKS) is a managed Kubernetes service that lets you deploy Kubernetes clusters without the complexities of handling the control plane and containerized infrastructure. Clusters are compatible with standard Kubernetes toolchains and integrate natively with DigitalOcean Load Balancers and block storage volumes.
The DigitalOcean Cloud Controller supports provisioning DigitalOcean Load Balancers in a cluster's resource configuration file. The DigitalOcean Load Balancer Service routes load balancer traffic to all worker nodes on the cluster. Only nodes configured to accept the traffic will pass health checks. Any other nodes will fail and show as unhealthy, but this is expected. Our community article, How to Set Up an Nginx Ingress with Cert-Manager on DigitalOcean Kubernetes, provides a detailed, practical example.
The example configuration below will define a load balancer and create it if one with the same name does not already exist. Additional configuration examples are available in the DigitalOcean Cloud Controller Manager repository.
You can add an external load balancer to a cluster by creating a new configuration file or adding the following lines to your existing service config file. Note that both the type and ports values are required for type: LoadBalancer:
annotations:
service.beta.kubernetes.io/do-loadbalancer-protocol: "http"
service.beta.kubernetes.io/do-loadbalancer-size-slug: "lb-large"
spec:
type: LoadBalancer
selector:
app: nginx-example
ports:
- name: http
protocol: TCP
port: 80
targetPort: 80
You can configure the size of the load balancer by setting an annotation with the appropriate slug size. In the context of a service file, this might look like:
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-example
annotations:
service.beta.kubernetes.io/do-loadbalancer-protocol: "http"
service.beta.kubernetes.io/do-loadbalancer-size-slug: "lb-large"
spec:
replicas: 2
selector:
matchLabels:
app: nginx-example
template:
metadata:
labels:
app: nginx-example
spec:
containers:
- name: nginx
image: nginx
ports:
- containerPort: 80
protocol: TCP
This is the minimum definition required to trigger creation of a DigitalOcean Load Balancer on your account and billing begins once the creation is completed. Currently, you cannot assign a floating IP address to a DigitalOcean Load Balancer.
Once you apply the config file to a deployment, use kubectl get services to see its status:
kubectl --kubeconfig=[full path to cluster config file] get services
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 192.0.2.1 <none> 443/TCP 2h
sample-load-balancer LoadBalancer 192.0.2.167 <pending> 80:32490/TCP 6s
When the load balancer creation is complete, <pending> will show the external IP address instead. In the PORT(S) column, the first port is the incoming port (80), and the second port is the node port (32490), not the container port supplied in the targetPort parameter.
To get detailed information about the load balancer configuration of a single load balancer, use kubectl's describe service command:
kubectl -kubeconfig=[full path to cluster config file] describe service [NAME]
Name: sample-load-balancer
Namespace: default
Labels: <none>
Annotations: kubectl.kubernetes.io/last-applied-configuration={"apiVersion":"v1","kind":"Service","metadata":{"annotations":{},"name":"sample-load-balancer","namespace":"default"},"spec":{"ports":[{"name":"https",...
Selector: <none>
Type: LoadBalancer
IP: 192.0.2.167
LoadBalancer Ingress: 203.0.113.86
Port: https 80/TCP
TargetPort: 443/TCP
NodePort: https 32490/TCP
Endpoints: <none>
Session Affinity: None
External Traffic Policy: Cluster
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal EnsuringLoadBalancer 3m (x2 over 38m) service-controller Ensuring load balancer
Normal EnsuredLoadBalancer 1m (x2 over 37m) service-controller Ensured load balancer
For more about managing load balancers, see:
Other Kubernetes Components in the DigitalOcean Community's Introduction to Kubernetes.
Kubernetes Services in the official Kubernetes Concepts guide