conkw documentation - ExternalInstanceGrabber

This is the EIG grabber, or external instance grabber. It will fetch metrics from other instances of conkw, and can even fetch metric from the current instance of conkw. One of the application is to have instances of conkw running on all your machines and one central instance producing a dashboard grouping all machines.

• Full name: net.pieroxy.conkw.webapp.grabbers.ExternalInstanceGrabber
• Default instance name: ext

Use cases

• You want to monitor all or some metrics from another running conkw instance.
• You want to monitor all or some metrics from many different conkw instance.

Operation

The configuration only parameter is the API URL that this instance needs to call. This is the same API that the UI calls to fetch data. For example:

{
  // External instance grabber. Grabs metrics from another live instance of conkw.
  "implementation":"net.pieroxy.conkw.webapp.grabbers.ExternalInstanceGrabber",
  "name":"test_eig",
  "config": {
    "url":"http://1.2.3.4:12789/api?grabbers=proc,sys",
    "credentialsRef":"TheUserCredentials"
  }
}

Where:

• 1.2.3.4 is the IP or host name of the computer on which conkw is running.
• 12789 is the port on which conkw is running on the computer 1.2.3.4.
• proc,sys is the grabbers that need to be fetched.
• credentialsRef Credentials for the remote API. Only needed if the remote api is authenticated. See all about credentials here for details.

The metrics extracted from both grabbers proc and sys are merged into one namespace, but prefixed with their grabber name. For example, the metric num.systemloadavg from the sys grabber will be renamed by EIG as num.sys_systemloadavg while the metric num.uptime from proc will be renamed num.proc_uptime.