Kong API Gateway

Introduction

Kong Gateway is a lightweight, fast, and flexible cloud-native API gateway. An API gateway is a reverse proxy that lets you manage, configure, and route requests to your APIs.

Getting Started

Compatibility

vuSmartMaps supports the monitoring of the Kong API Gateway metric using prometheus endpoint.

Data Collection Method

vuSmartMaps collects health and performance data for Kong API Gateway using VuNet's Internal Data Collector.

Prerequisites

Inputs for Configuring Data Source

• Kong API Server: The IP Address/FQDN of the Kong API server. This field is the key to identify each server you add here.
• Kong Server's Endpoint: The URL to Kong API Server endpoint. Eg: http://127.0.0.1, https://127.0.0.1, http://127.0.0.1:8080 or https://127.0.0.1:8080
• Period (in seconds): Time interval for polling data from the Kong API Server. Period should be between 60 seconds – 3000 seconds.

Firewall Requirement

To collect data from this O11ySource, ensure the following ports are opened:

Source IP	Destination IP	Destination Port	Protocol	Direction
vuSmartMaps IP	Kong API Gateway	8101*	TCP	Outbound

*Before providing the firewall requirements, please update the port based on the customer environment.

Configuring the Target

Option 1 - Recommended Approach Using Status API

Step 1: Enable the Status API

Edit

kong.conf:

status_listen = 0.0.0.0:8100

Alternatively, using environment variables:

export KONG_STATUS_LISTEN=0.0.0.0:8100

Restart Kong:

kong restart

Step 2: Enable the Prometheus Plugin

Execute the following command:

curl -i -X POST http://localhost:8001/plugins
--data "name=prometheus"

Expected response:

{ "name": "prometheus", "enabled": true }

Step 3: Verify the Metrics Endpoint

Access the metrics endpoint:

curl http://localhost:8100/metrics

Expected output:

HELP kong_http_status HTTP status codes

TYPE kong_http_status counter

To monitor Kong Data Plane (DP) in a Hybrid deployment with Konnect:

Enable the Prometheus plugin:

The Prometheus plugin must be enabled (globally or for the desired services/routes) via Konnect so that the Data Plane exposes Kong metrics.

Enable the Status API:

Configure the Data Plane to expose the Status API, for example:

KONG_STATUS_LISTEN=0.0.0.0:8100

The metrics endpoint will then be:

http://<data-plane-host>:8100/metrics

Additional requirements:

Network access: The vuSmartMaps Server must be able to reach the Data Plane's Status API port (for example, 8100). Ensure firewalls, security groups, and Kubernetes network policies (if applicable) allow access.

Authentication (if configured): If the /metrics endpoint is protected, configure vuSmartMaps Server with the required authentication (headers, mTLS, etc.).

One scrape target per Data Plane: Each Data Plane exposes its own local metrics. Configure vuSmartMaps Server to scrape every Data Plane node; there is no central metrics endpoint that aggregates all DPs.

Option 2 - Access Metrics via Admin API

If the Status API is not enabled, metrics can also be accessed through the Admin API endpoint.

Metrics URL:

http://localhost:8001/metrics

Verification command:

curl http://localhost:8001/metrics

Note: Using the Admin API endpoint for metrics exposure is not recommended in production environments.

Configuration Steps

• Enable the O11ySource.
• Select the sources tab and press the + button to add a new instance that has to be monitored.
• Provide the required configurations:
• *Kong API Server
• *Kong Server's Endpoint
• *Period (in seconds)
• Click Save to close the data source window.

Metrics Collected

Name	Description	Data Type
@timestamp	Timestamp at which the data is collected by agent	String
timestamp	Precise event timestamp with milliseconds	DateTime64(3)
target	Server from where the data is collected	String
tags_host	Server from where the data is collected	String
doc_type	Document type of the entry	String
tenant_id	Tenant ID for the metrics entry	LowCardinality(String)
bu_id	Business Unit ID for the entry	LowCardinality(String)
tags_url	URL endpoint from where the request is being made	String
tags_service	Service name related to the API	String
tags_route	Route associated with the API	String
tags_direction	Direction of the API call (inbound/outbound)	String
tags_code	HTTP status code	UInt16
tags_shared_dict	Shared dictionary in use	String
tags_subsystem	Subsystem generating the metric	String
tags_kong_subsystem	Kong subsystem	String
tags_state	State of the request	String
tags_node_id	Node ID of the Kong instance	String
metric_name	Name of the metric being recorded	String
metric_value	Value of the recorded metric	Float64
metric_value_diff	Difference in metric value	Float64
tags_pid	Process ID of the Kong instance	UInt32
host	Host on which Kong is running	String
Port	Port of the Kong instance	String
tags_target	Target of the upstream service	String
tags_upstream	Upstream service in the request	String
tags_address	Address of the service or host	String