NGINX Exporter Metrics

NGINX Exporter Metrics input plugin scrapes metrics from the NGINX stub status handler.

Configuration Parameters

The plugin supports the following configuration parameters:

Getting Started

NGINX must be configured with a location that invokes the stub status handler. Here is an example configuration with such a location:

server {
    listen       80;
    listen  [::]:80;
    server_name  localhost;
    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm;
    }
    // configure the stub status handler.
    location /status {
        stub_status;
    }
}

Configuration with NGINX Plus REST API

A much more powerful and flexible metrics API is available with NGINX Plus. A path needs to be configured in NGINX Plus first.

server {
	listen       80;
	listen  [::]:80;
	server_name  localhost;

	# enable /api/ location with appropriate access control in order
	# to make use of NGINX Plus API
	#
	location /api/ {
		api write=on;
		# configure to allow requests from the server running fluent-bit
		allow 192.168.1.*;
		deny all;
	}
}

Command Line

From the command line you can let Fluent Bit generate the checks with the following options:

$ fluent-bit -i nginx_metrics -p host=127.0.0.1 -p port=80 -p status_url=/status -p nginx_plus=off -o stdout

To gather metrics from the command line with the NGINX Plus REST API we need to turn on the nginx_plus property, like so:

$ fluent-bit -i nginx_metrics -p host=127.0.0.1 -p port=80 -p nginx_plus=on -p status_url=/api -o stdout

Configuration File

In your main configuration file append the following Input & Output sections:

[INPUT]
    Name          nginx_metrics
    Host          127.0.0.1
    Port          80
    Status_URL    /status
    Nginx_Plus    off

[OUTPUT]
    Name   stdout
    Match  *

And for NGINX Plus API:

[INPUT]
    Name          nginx_metrics
    Nginx_Plus    on
    Host          127.0.0.1
    Port          80
    Status_URL    /api

[OUTPUT]
    Name   stdout
    Match  *

Testing

You can quickly test against the NGINX server running on localhost by invoking it directly from the command line:

$ fluent-bit -i nginx_metrics -p host=127.0.0.1 -p nginx_plus=off -o stdout -p match=* -f 1
Fluent Bit v1.x.x
* Copyright (C) 2019-2020 The Fluent Bit Authors
* Copyright (C) 2015-2018 Treasure Data
* Fluent Bit is a CNCF sub-project under the umbrella of Fluentd
* https://fluentbit.io

2021-10-14T19:37:37.228691854Z nginx_connections_accepted = 788253884
2021-10-14T19:37:37.228691854Z nginx_connections_handled = 788253884
2021-10-14T19:37:37.228691854Z nginx_http_requests_total = 42045501
2021-10-14T19:37:37.228691854Z nginx_connections_active = 2009
2021-10-14T19:37:37.228691854Z nginx_connections_reading = 0
2021-10-14T19:37:37.228691854Z nginx_connections_writing = 1
2021-10-14T19:37:37.228691854Z nginx_connections_waiting = 2008
2021-10-14T19:37:35.229919621Z nginx_up = 1

Exported Metrics

This documentation is copied from the nginx prometheus exporter metrics documentation: [https://github.com/nginxinc/nginx-prometheus-exporter/blob/master/README.md].

Common metrics:

Metrics for NGINX OSS:

Stub status metrics

Metrics for NGINX Plus:

Connections

HTTP

SSL

HTTP Server Zones

Stream Server Zones

HTTP Upstreams

Note: for the state metric, the string values are converted to float64 using the following rule: "up" -> 1.0, "draining" -> 2.0, "down" -> 3.0, "unavail" –> 4.0, "checking" –> 5.0, "unhealthy" -> 6.0.

Stream Upstreams

Note: for the state metric, the string values are converted to float64 using the following rule: "up" -> 1.0, "down" -> 3.0, "unavail" –> 4.0, "checking" –> 5.0, "unhealthy" -> 6.0.

Location Zones