
# Nginx by HTTP

## Overview

This template is developed to monitor Nginx by Zabbix that works without any external scripts.
Most of the metrics are collected in one go, thanks to Zabbix bulk data collection.

The template collects metrics by polling the module [`ngx_http_stub_status_module`](https://nginx.ru/en/docs/http/ngx_http_stub_status_module.html) with HTTP agent remotely:

```text
Active connections: 291
server accepts handled requests
16630948 16630948 31070465
Reading: 6 Writing: 179 Waiting: 106
```

## Requirements

Zabbix version: 7.4 and higher.

## Tested versions

This template has been tested on:
- Nginx 1.17.2 

## Configuration

> Zabbix should be configured according to the instructions in the [Templates out of the box](https://www.zabbix.com/documentation/7.4/manual/config/templates_out_of_the_box) section.

## Setup

1. See the setup instructions for [`ngx_http_stub_status_module`](https://nginx.ru/en/docs/http/ngx_http_stub_status_module.html).

Test the availability of the `http_stub_status_module` with `nginx -V 2>&1 | grep -o with-http_stub_status_module`.

Example configuration of Nginx:

```text
location = /basic_status {
    stub_status;
    allow <IP of your Zabbix server/proxy>;
    deny all;
}
```

2. Set the hostname or IP address of the Nginx host or Nginx container in the `{$NGINX.STUB_STATUS.HOST}` macro. You can also change the status page port in the `{$NGINX.STUB_STATUS.PORT}` macro, the status page scheme in the `{$NGINX.STUB_STATUS.SCHEME}` macro and the status page path in the `{$NGINX.STUB_STATUS.PATH}` macro if necessary.

Example answer from Nginx:

```text
Active connections: 291
server accepts handled requests
16630948 16630948 31070465
Reading: 6 Writing: 179 Waiting: 106
```

### Macros used

|Name|Description|Default|
|----|-----------|-------|
|{$NGINX.STUB_STATUS.HOST}|<p>The hostname or IP address of the Nginx host or Nginx container of a stub_status.</p>||
|{$NGINX.STUB_STATUS.SCHEME}|<p>The protocol http or https of Nginx stub_status host or container.</p>|`http`|
|{$NGINX.STUB_STATUS.PATH}|<p>The path of the `Nginx stub_status` page.</p>|`basic_status`|
|{$NGINX.STUB_STATUS.PORT}|<p>The port of the `Nginx stub_status` host or container.</p>|`80`|
|{$NGINX.RESPONSE_TIME.MAX.WARN}|<p>The maximum response time of Nginx expressed in seconds for a trigger expression.</p>|`10`|
|{$NGINX.DROP_RATE.MAX.WARN}|<p>The critical rate of the dropped connections for a trigger expression.</p>|`1`|

### Items

|Name|Description|Type|Key and additional info|
|----|-----------|----|-----------------------|
|Get stub status page|<p>The following status information is provided:</p><p>`Active connections` - the current number of active client connections including waiting connections.</p><p>`Accepted` - the total number of accepted client connections.</p><p>`Handled` - the total number of handled connections. Generally, the parameter value is the same as for the accepted connections, unless some resource limits have been reached (for example, the `worker_connections` limit).</p><p>`Requests` - the total number of client requests.</p><p>`Reading` - the current number of connections where Nginx is reading the request header.</p><p>`Writing` - the current number of connections where Nginx is writing a response back to the client.</p><p>`Waiting` - the current number of idle client connections waiting for a request.</p><p></p><p>See also [Module ngx_http_stub_status_module](https://nginx.org/en/docs/http/ngx_http_stub_status_module.html).</p>|HTTP agent|nginx.get_stub_status|
|Service status||Simple check|net.tcp.service[http,"{$NGINX.STUB_STATUS.HOST}","{$NGINX.STUB_STATUS.PORT}"]<p>**Preprocessing**</p><ul><li><p>Discard unchanged with heartbeat: `10m`</p></li></ul>|
|Service response time||Simple check|net.tcp.service.perf[http,"{$NGINX.STUB_STATUS.HOST}","{$NGINX.STUB_STATUS.PORT}"]|
|Requests total|<p>The total number of client requests.</p>|Dependent item|nginx.requests.total<p>**Preprocessing**</p><ul><li><p>Regular expression: `The text is too long. Please see the template.`</p></li></ul>|
|Requests per second|<p>The total number of client requests.</p>|Dependent item|nginx.requests.total.rate<p>**Preprocessing**</p><ul><li><p>Regular expression: `The text is too long. Please see the template.`</p></li><li>Change per second</li></ul>|
|Connections accepted per second|<p>The total number of accepted client connections.</p>|Dependent item|nginx.connections.accepted.rate<p>**Preprocessing**</p><ul><li><p>Regular expression: `The text is too long. Please see the template.`</p></li><li>Change per second</li></ul>|
|Connections dropped per second|<p>The total number of dropped client connections.</p>|Dependent item|nginx.connections.dropped.rate<p>**Preprocessing**</p><ul><li><p>JavaScript: `The text is too long. Please see the template.`</p></li><li>Change per second</li></ul>|
|Connections handled per second|<p>The total number of handled connections. Generally, the parameter value is the same as for the accepted connections, unless some resource limits have been reached (for example, the `worker_connections limit`).</p>|Dependent item|nginx.connections.handled.rate<p>**Preprocessing**</p><ul><li><p>Regular expression: `The text is too long. Please see the template.`</p></li><li>Change per second</li></ul>|
|Connections active|<p>The current number of active client connections including waiting connections.</p>|Dependent item|nginx.connections.active<p>**Preprocessing**</p><ul><li><p>Regular expression: `Active connections: ([0-9]+) \1`</p></li></ul>|
|Connections reading|<p>The current number of connections where Nginx is reading the request header.</p>|Dependent item|nginx.connections.reading<p>**Preprocessing**</p><ul><li><p>Regular expression: `Reading: ([0-9]+) Writing: ([0-9]+) Waiting: ([0-9]+) \1`</p></li></ul>|
|Connections waiting|<p>The current number of idle client connections waiting for a request.</p>|Dependent item|nginx.connections.waiting<p>**Preprocessing**</p><ul><li><p>Regular expression: `Reading: ([0-9]+) Writing: ([0-9]+) Waiting: ([0-9]+) \3`</p></li></ul>|
|Connections writing|<p>The current number of connections where Nginx is writing a response back to the client.</p>|Dependent item|nginx.connections.writing<p>**Preprocessing**</p><ul><li><p>Regular expression: `Reading: ([0-9]+) Writing: ([0-9]+) Waiting: ([0-9]+) \2`</p></li></ul>|
|Version||Dependent item|nginx.version<p>**Preprocessing**</p><ul><li><p>Regular expression: `(?i)Server: nginx\/(.+(?<!\r)) \1`</p></li><li><p>Discard unchanged with heartbeat: `1d`</p></li></ul>|

### Triggers

|Name|Description|Expression|Severity|Dependencies and additional info|
|----|-----------|----------|--------|--------------------------------|
|Nginx: Failed to fetch stub status page|<p>Zabbix has not received any data for items for the last 30 minutes.</p>|`find(/Nginx by HTTP/nginx.get_stub_status,,"iregexp","HTTP\\/[\\d.]+\\s+200")=0 or nodata(/Nginx by HTTP/nginx.get_stub_status,30m)=1`|Warning|**Manual close**: Yes<br>**Depends on**:<br><ul><li>Nginx: Service is down</li></ul>|
|Nginx: Service is down||`last(/Nginx by HTTP/net.tcp.service[http,"{$NGINX.STUB_STATUS.HOST}","{$NGINX.STUB_STATUS.PORT}"])=0`|Average|**Manual close**: Yes|
|Nginx: Service response time is too high||`min(/Nginx by HTTP/net.tcp.service.perf[http,"{$NGINX.STUB_STATUS.HOST}","{$NGINX.STUB_STATUS.PORT}"],5m)>{$NGINX.RESPONSE_TIME.MAX.WARN}`|Warning|**Manual close**: Yes<br>**Depends on**:<br><ul><li>Nginx: Service is down</li></ul>|
|Nginx: High connections drop rate|<p>The rate of dropping connections has been greater than {$NGINX.DROP_RATE.MAX.WARN} for the last 5 minutes.</p>|`min(/Nginx by HTTP/nginx.connections.dropped.rate,5m) > {$NGINX.DROP_RATE.MAX.WARN}`|Warning|**Depends on**:<br><ul><li>Nginx: Service is down</li></ul>|
|Nginx: Version has changed|<p>The Nginx version has changed. Acknowledge to close the problem manually.</p>|`last(/Nginx by HTTP/nginx.version,#1)<>last(/Nginx by HTTP/nginx.version,#2) and length(last(/Nginx by HTTP/nginx.version))>0`|Info|**Manual close**: Yes|

## Feedback

Please report any issues with the template at [`https://support.zabbix.com`](https://support.zabbix.com)

You can also provide feedback, discuss the template, or ask for help at [`ZABBIX forums`](https://www.zabbix.com/forum/zabbix-suggestions-and-feedback)

