AppDynamics Nginx Monitoring Extension

Use Case

Nginx is a web server which can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache. The Nginx monitoring extension gets metrics from the nginx server and displays them in the AppDynamics Metric Browser. This extension supports both NGinx and NGinx Plus.

Prerequisites

1. Before the extension is installed, the prerequisites mentioned here need to be met. Please do not proceed with the extension installation if the specified prerequisites are not met.
2. The extension needs to be able to connect to the Nginx in order to collect and send metrics. To do this, you will have to either establish a remote connection in between the extension and the product, or have an agent on the same machine running the product in order for the extension to collect and send the metrics.

Installation

Note: For the following steps to work, nginx should be running with "ngx_http_stub_status_module" or "ngx_http_api_module" enabled. Please make sure you have required changes in the nginx.conf.

1. Run 'mvn clean install' from "nginx-monitoring-extension"
2. Unzip the nginx-monitoring-extension-<VERSION>.zip from target directory into the "<MachineAgent_Dir>/monitors" directory.
3. Edit the file config.yml as described below in Configuration Section, located in <MachineAgent_Dir>/monitors/NginxMonitor and update the server(s) details.
4. All metrics to be reported are configured in metrics.xml. Users can remove entries from metrics.xml to stop the metric from reporting, or add new entries as well.
5. Restart the Machine Agent.

Please place the extension in the "monitors" directory of your Machine Agent installation directory. Do not place the extension in the "extensions" directory of your Machine Agent installation directory.

Directory Structure

Configuration

Config.yml

Configure the extension by editing the config.yml file in <MACHINE_AGENT_HOME>/monitors/NginxMonitor/.

1. Configure the "COMPONENT_ID" under which the metrics need to be reported. This can be done by changing the value of <COMPONENT_ID> in metricPrefix: Server|Component:<TIER_ID>|Custom Metrics|Nginx|.
   For example,

    metricPrefix:  "Server|Component:100>|Custom Metrics|Nginx|"
   

More details around metric prefix can be found here.

2. The extension supports reporting metrics from multiple Nginx instances. The monitor provides an option to add Nginx server/s for monitoring the metrics provided by the particular end-point. Have a look at config.yml for more details.
   For example:

     metricPrefix:  "Server|Component:<TIER_ID>|Custom Metrics|Nginx|"
   
     servers:
       - displayName: "Nginx Server" # mandatory
         uri: "http://localhost/nginx_status" # append port if needed
   # uri: "http://demo.nginx.com/" # when nginx_plus equals true
         username: ""
         password: ""
         encryptedPassword:
         nginx_plus: "false"  # true for nginx plus else false
   
     encryptionKey: ""
   
     connection:
       sslCertCheckEnabled: false
       socketTimeout: 10000
       connectTimeout: 10000
   
      # For each server you monitor, you will need a total of 8(by default) thread.
      # By default we want to support 5 servers, so it is 5 * 8 = 40 threads.
     numberOfThreads: 12
   

3. If you want to monitor nginx plus then put nginx_plus as true and make sure ngx_http_api_module is configured.

        nginx_plus: "true"  # true for nginx plus else false
   

   NOTE: When you want to monitor Nginx Plus, then the uri should not have the nginx_status. uri should be the Hostname/IP as below.

        uri: "http://demo.nginx.com/"
   

4. Configure the numberOfThreads.
   For example,
   If number of servers that need to be monitored is 5, then number of threads required is 5 * 12 = 60

   numberOfThreads: 60
   

Metrics.xml

You can add/remove metrics of your choice by modifying the provided metrics.xml file. This file consists of all the metrics that will be monitored and sent to the controller. Please look how the metrics have been defined and follow the same convention, when adding new metrics. You do have the ability to chosoe your Rollup types as well as set an alias that you would like to be displayed on the metric browser.

1. Stats Configuration
   Add the stats url which has api version(1/2/3) information as shown below.

   <stats url="/api/3">
   

2. Metric Stat Configuration
   Add the metric to be monitored under the metric tag as shown below.

   <stat suburl="processes" name="Processes-Status">
       <metric attr="respawned" alias="Respawned" aggregationType = "AVERAGE" timeRollUpType = "AVERAGE" clusterRollUpType = "COLLECTIVE"/>
   </stat>
   

For configuring the metrics, the following properties can be used:

All these metric properties are optional, and the default value shown in the table is applied to the metric (if a property has not been specified) by default.

Metrics

Nginx Monitoring Extension can collect metric by hitting the available Endpoints which are configured in the metrics.xml.

Nginx Metrics

Nginx Plus Metrics

Requests

Server Zones

Upstreams

Connections

Caches

Credentials Encryption

Please visit this page to get detailed instructions on password encryption. The steps in this document will guide you through the whole process.

Extensions Workbench

Workbench is an inbuilt feature provided with each extension in order to assist you to fine tune the extension setup before you actually deploy it on the controller. Please review the following document on How to use the Extensions WorkBench.

Troubleshooting

Please follow the steps listed in this troubleshooting-document in order to troubleshoot your issue. These are a set of common issues that customers might have faced during the installation of the extension.

Contributing

Always feel free to fork and contribute any changes directly here on GitHub.

Version

Note: While extensions are maintained and supported by customers under the open-source licensing model, they interact with agents and Controllers that are subject to AppDynamics’ maintenance and support policy. Some extensions have been tested with AppDynamics 4.5.13+ artifacts, but you are strongly recommended against using versions that are no longer supported.