Exposing services with load balancers

You can expose a Kubernetes service in your Managed Service for Kubernetes cluster using a load balancer. The load balancer receives traffic on a public or private IP address, depending on how you set it up, and distributes the traffic between the service’s Pods automatically.

Requirements to connect to a VM with private IP addressTo connect to a Managed Service for Kubernetes cluster from a Compute VM using a private IP address or another cluster using a private load balancer, both must be in the same region and subnet.

Prerequisites

Before you start setting up a load balancer, you need to create a Managed Kubernetes cluster and connect to it using kubectl.

Load balancers types

By default, load balancers are created with public IP addresses. To expose your service on a private IP address instead, add nebius.com/load-balancer-type: internal to the annotations of the service.

To retain an IP address that was automatically allocated to a load balancer and reuse it after deleting or recreating the service, follow the How to convert a dynamically assigned public IP address to a reusable allocation guide.

If you have created an IP address allocation (example for public IP addresses) and want to use it to allocate an IP address to a load balancer, add its ID to the service annotation nebius.com/load-balancer-allocation-id. The allocation type (public or private) must match the load balancer type. The table below explains how these two annotations work together:

Type is `internal`	Allocation ID is set	Result
Yes	Yes	Load balancer gets a private IP address from the provided allocation
Yes	No	Load balancer gets a private IP address from a new allocation
No	Yes	Load balancer gets a public IP address from the provided allocation
No	No	Load balancer gets a public IP address from a new allocation

To allocate a public IP address from a specific IP pool, add the pool ID to the nebius.com/load-balancer-pool-id service annotation. When this annotation is set, the IP address is allocated from the specified pool instead of the default user subnet pool. For more information about IP pools, see the Virtual Networks overview.

annotations:
  nebius.com/load-balancer-pool-id: "<pool_ID>"

How to set up a load balancer

With a private IP address
With a public IP address

Create the manifest to set up the internal load balancer service with a private IP address (we will refer to it later as service.yaml):

apiVersion: v1
kind: Service
metadata:
  name: nginx
  annotations:
    nebius.com/load-balancer-type: "internal"
spec:
  selector:
    app: nginx
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80
  type: LoadBalancer

Create the manifest for nginx deployment (we will refer to it later as deployment.yaml):

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - containerPort: 80

Apply the configurations:

kubectl apply -f deployment.yaml
kubectl apply -f service.yaml

Check the service and the allocated IP address:

kubectl get svc nginx

You will receive an output like the one below:

NAME         TYPE           CLUSTER-IP       EXTERNAL-IP     PORT(S)        AGE
nginx        LoadBalancer   10.158.250.188   192.168.0.112   80:30512/TCP   4s

Create the manifest to set up the internal load balancer service with a public IP address (we will refer to it later as service.yaml):

apiVersion: v1
kind: Service
metadata:
  name: nginx
spec:
  selector:
    app: nginx
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80
  type: LoadBalancer

Create the manifest for nginx deployment (we will refer to it later as deployment.yaml):

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - containerPort: 80

Apply the configurations:

kubectl apply -f deployment.yaml
kubectl apply -f service.yaml

Check the service and the allocated IP address:

kubectl get svc nginx

You will see an output like the one below:

NAME    TYPE           CLUSTER-IP      EXTERNAL-IP     PORT(S)        AGE
nginx   LoadBalancer   10.158.105.48   195.242.8.219   80:30816/TCP   13s

Use the EXTERNAL-IP from the previous command output to connect to the service from outside of the Kubernetes cluster:
curl -i <EXTERNAL-IP>
You will see an output like the one below:
HTTP/1.1 200 OK Server: nginx/1.27.1

Virtual machines

Slurm and Soperator in Nebius AI Cloud

Managed Service for Kubernetes®

Exposing services with load balancers

Prerequisites

Load balancers types

How to set up a load balancer

​Prerequisites

​Load balancers types

​How to set up a load balancer

Prerequisites

Load balancers types

How to set up a load balancer