Creating a network load balancer using an NGINX Ingress controller

When installing an NGINX Ingress controller, you can create an external or internal network load balancer and set up port forwarding.

Getting startedGetting started

1. Create a service account with the editor, container-registry.images.puller, and load-balancer.admin roles for the folder. The load-balancer.admin role is required to create a network load balancer.

2. Create security groups for the Managed Service for Kubernetes cluster and its node groups.

   Warning

   The configuration of security groups determines the performance and availability of the cluster and the services and applications running in it.

3. Create a Managed Service for Kubernetes cluster. In the cluster settings, specify the service account and the security groups created earlier.

4. Install Helm v3.8.0 or higher.

5. Install kubectl and configure it to work with the created cluster.

6. Set up Helm to work with the NGINX repository:

   1. Add a repository for NGINX to Helm:

      helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
      

      Result:

      "ingress-nginx" has been added to your repositories
      

   2. Update the dataset to create an application instance in the Managed Service for Kubernetes cluster:

      helm repo update
      

      Result:

      Hang tight while we grab the latest from your chart repositories...
      ...Successfully got an update from the "ingress-nginx" chart repository
      Update Complete. ⎈Happy Helming!⎈
      

   Tip

   You can also install an NGINX Ingress controller using Yandex Cloud Marketplace.

External network load balancerExternal network load balancer

An external network load balancer is created when installing an NGINX Ingress controller in a standard configuration:

helm install ingress-nginx ingress-nginx/ingress-nginx

Result:

NAME: ingress-nginx
LAST DEPLOYED: Sun Jul 18 22:35:37 2022
NAMESPACE: default
...
The ingress-nginx controller has been installed.
It may take a few minutes for the LoadBalancer IP to be available.
You can watch the status by running 'kubectl --namespace default get services -o wide -w ingress-nginx-controller'
...

Internal network load balancerInternal network load balancer

To install an internal network load balancer:

1. Configure the controller. To do this, create a configuration file named values.yaml and specify in it the ID of the subnet the network load balancer should operate in:

   controller:
     service:
       external:
         enabled: false
       internal:
         enabled: true
         annotations:
           yandex.cloud/load-balancer-type: internal
           yandex.cloud/subnet-id: <subnet_ID>
   

2. Install a NGINX Ingress controller using the values.yaml configuration file:

   helm install ingress-nginx -f values.yaml ingress-nginx/ingress-nginx
   

   Result:

   NAME: ingress-nginx
   LAST DEPLOYED: Sun Jul 18 22:55:37 2022
   NAMESPACE: default
   ...
   The ingress-nginx controller has been installed.
   It may take a few minutes for the LoadBalancer IP to be available.
   You can watch the status by running 'kubectl --namespace default get services -o wide -w ingress-nginx-controller'
   ...
   

Check the resultCheck the result

To make sure the network load balancer was created, get a list of network load balancers in the folder.

Port forwardingPort forwarding

Even though NGINX Ingress controllers officially support external HTTP and HTTPS traffic routing only, you can configure them to accept external TCP or UDP traffic and redirect it to internal services. To do this, install an Ingress controller using the values.yaml configuration file with traffic redirect settings and portNamePrefix.

1. Create a file named values.yaml:

   <protocol>: {<external_port>: "<service_namespace>/<service_name>:<internal_port>"}
   portNamePrefix: "<prefix>"
   

   Where <protocol> is the protocol, tcp or udp.

2. Install a NGINX Ingress controller using the values.yaml configuration file:

   helm install ingress-nginx -f values.yaml ingress-nginx/ingress-nginx
   

Example

Let's say we need to set up traffic forwarding with the following parameters:

• Service name: example-go.
• Service namespace: default.
• Internal service port: 8080.
• External port: 9000.
• Port name prefix: test.

values.yaml configuration file for such forwarding:

tcp: {9000: "default/example-go:8080"}
portNamePrefix: "test"

After you install the Ingress controller, the new network load balancer will have an additional listener, test-9000-tcp, with the forwarding settings you specified.

The names of the NGINX Ingress controller's port and network load balancer's listener are based on the forwarding settings: <external_port>-<protocol>. Due to Yandex Cloud's limitations, the listener's name may not start with numbers, so prefix it with portNamePrefix to ensure the settings are correct. The port and listener names will thus be generated in <portNamePrefix_value>-<external_port>-<protocol> format.

Due to technical limitations, the port name is limited to 15 characters and the listener name must not start with numbers. Therefore, make sure that your portNamePrefix prefix:

• Starts with letters.
• Is no longer than 5-8 characters, depending on the external port value length.

To make sure that port forwarding is configured properly, view the list of listeners in the network load balancer details.