Nginx¶

The nginx probe monitors Nginx by scraping the ngx_http_stub_status_module status page, reporting active connections, request throughput and connection state breakdown (reading, writing, waiting).

Quick start¶

# probes.d/20-nginx.yaml — each file under probes.d/ is a YAML array of probes
- name: nginx
  type: nginx
  params:
    endpoint: http://localhost/nginx_status

Parameters¶

Parameter	Must set	Default	Description
`endpoint`	In practice	`http://localhost/nginx_status`	URL of the stub_status page
`interval`	No	`60`	Seconds between collections
`timeout`	No	`10`	Request timeout in seconds
`instance_name`	No	-	Stable identity of this server; set it when two nginx probes run on one host

Metrics¶

Metric	Unit	Description
`senhub.nginx.up`	1	1 when the stub_status page is reachable and parseable
`nginx.connections.current`	{connection}	Active connections currently being handled
`nginx.connections.accepted`	{connection}	Total connections accepted since nginx started (monotonic)
`nginx.connections.handled`	{connection}	Total connections handled since start
`nginx.requests`	{request}	Total HTTP requests handled since start
`nginx.connections.reading`	{connection}	Connections reading the request header
`nginx.connections.writing`	{connection}	Connections writing the response
`nginx.connections.waiting`	{connection}	Idle keep-alive connections waiting for a request

Operational notes¶

Enable ngx_http_stub_status_module and expose it in nginx.conf:

location /nginx_status {
    stub_status;
    allow 127.0.0.1;
    deny all;
}

The module is included in most Nginx packages by default; verify with nginx -V 2>&1 | grep stub_status.
nginx.connections.accepted, nginx.connections.handled and nginx.requests are monotonically increasing counters since the last Nginx reload.

Metric reference¶

Every metric this probe can emit. Metric is the OpenTelemetry name the OTLP, Prometheus and Zabbix outputs derive theirs from. Name is what a Nagios check and the API metrics= filter match. PRTG channel is the label PRTG shows, placeholders filled from the series' tags.

Metric	Name	PRTG channel	Unit	Description
`senhub.nginx.up`	`senhub.nginx.up`	Nginx Up	#	1 when the stub_status page is reachable and parseable, 0 otherwise
`nginx.connections.current`	`nginx.connections.current`	Nginx Active Connections	#	Number of client connections currently being handled (accepted + in-flight)
`nginx.connections.accepted`	`nginx.connections.accepted`	Nginx Accepted Connections	#	Total connections accepted since nginx start (monotonically increasing counter)
`nginx.connections.handled`	`nginx.connections.handled`	Nginx Handled Connections	#	Total connections handled since nginx start; equals accepted when no resource limit is hit
`nginx.requests`	`nginx.requests`	Nginx Total Requests	#	Total HTTP requests processed since nginx start
`nginx.connections.reading`	`nginx.connections.reading`	Nginx Reading Connections	#	Connections where nginx is reading the request header
`nginx.connections.writing`	`nginx.connections.writing`	Nginx Writing Connections	#	Connections where nginx is writing the response to the client
`nginx.connections.waiting`	`nginx.connections.waiting`	Nginx Waiting Connections	#	Idle keep-alive connections waiting for a request