Gcore collects and stores metrics and logs from various cloud resources, including load balancers. This guide explains the different monitoring features and how to configure them for an existing load balancer.

Prometheus listener

Load balancers use listeners to associate a port with a pool of instances. In addition to the regular balancing listeners, you can create one that exposes an endpoint with the balancer’s metrics. This enables you to scrape them with Prometheus and view them with Grafana.

Tip: Import this pre-made Grafana dashboard to display your metrics.

Enable Prometheus listener

You can enable the Prometheus listener from the Customer Portal by following these steps:

1

Open the listener settings

To enable the metrics endpoint, open the Gcore Customer Portal, navigate to Cloud > Networking > Load Balancers, and click the name of a load balancer in the list.

This will take you to the Load Balancer Details page.

2

Initialize the listener creation

Select the Listeners tab, scroll down until you see the Add Listener button, and click it.

This will open the Add Listener dialog.

3

Configure the listener

Enter a Name for your listener, set a Port and a Connection limit, and for the Protocol select Prometheus

Just like with regular listeners, you have the following options to secure your Prometheus listener:

4

Finalize the listener

Click the Create Listener button and wait until the Prometheus listener appears in the list.

You can now add the listener as a target to a Prometheus instance by adding the following lines to its prometheus.yml under the scrape_configs section:

- job_name: <LOAD_BALANCER_NAME>
    metrics_path: /metrics
    static_configs:
    - targets:
      - <LOAD_BALANCER_IP>:<PROMETHEUS_LISTENER_PORT>

Disable Prometheus listener

Before you delete a Prometheus listener, you should delete the corresponding job from all prometheus.yml files.

You can disable the Prometheus listener in the Customer Portal by following these steps:

1

Open the load balancer settings

Open the Gcore Customer Portal, navigate to Cloud > Networking > Load Balancers, and click a load balancer’s name in the list.

2

Delete the listener

Select the Listeners tab, scroll down until you see the Prometheus listener, click on its corresponding action menu on the right, and click Delete.

Logging as a service

Gcore offers Managed Logging, also known as logging as a service (LaaS) for all cloud resources. 

When you enable logging on a load balancer, LaaS will store the logs in the same region as the load balancer.

Enable logging

You can enable logging via the Customer Portal by following these steps:

1

Open the load balancer settings

To enable the logging, open the Gcore Customer Portal, navigate to Cloud > Networking > Load Balancers, and click the name of a load balancer in the list.

2

Initialize logging

Select the Logging tab, and activate the Enable Logging toggle.

You can either use an existing log Topic or create a new one, allowing you to define a Retention period.

3

Finalize logging

Click the Save changes button, and Gcore’s LaaS will set up the logging for the load balancer.

View the logs

You can now view your logs in the Customer Portal or your own Grafana instance. To view the logs in the Customer Portal, follow these steps:

1

Open Managed Logging

Open the Gcore Customer Portal and navigate to Cloud > Managed Logging.

2

Open OpenSearch dashboard

Select a log topic from the list and click the corresponding View Logs link.

Disable logging

You can disable logging via the Customer Portal by following these steps:

1

Open the load balancer settings

Open the Gcore Customer Portal, navigate to Cloud > Networking > Load Balancers, and click a load balancer’s name in the list.

2

Deactivate logging

Select the Logging tab, deactivate the Enable Logging toggle, and click the Save changes button.

Cloud API endpoints

You can request status, metrics, and general statistics for your load balancers via the Gcore Cloud API.

Load balancer status

The status endpoints provide details about a load balancer’s operating and provisioning status, its listeners, and their pools.

You can find more information about the endpoints on the following documentation pages.

Load balancer metrics

The metrics endpoint provides information about CPU, memory, and network utilization.

You can find more information about the endpoints on the following documentation pages.

Load balancer and listener statistics

The get endpoints for load balancers and listeners provide data about connections, traffic, and errors when called with ?show_stats=true.

You can find more information about the endpoints on the following documentation pages.