5 Descubrimiento de objetos JMX

Descripción general

Es posible descubrir todos los atributos JMX MBeans o de MBean o para especificar un patrón para el descubrimiento de estos objetos.

Es obligatorio comprender la diferencia entre un MBean y un atributo MBean para la configuración de reglas de descubrimiento. Un MBean es un objeto que puede representar un dispositivo, una aplicación o cualquier recurso que deba ser administrado.

Por ejemplo, hay un MBean que representa un servidor web. Sus atributos son recuento de conexiones, recuento de subprocesos, tiempo de espera de solicitud, caché de archivos http, uso de memoria, etc. Expresando este pensamiento en un lenguaje humano comprensible podemos decir que una máquina de café es como un MBean que tiene los siguientes atributos a monitorear: cantidad de agua por taza, consumo medio de agua durante un determinado período de tiempo, número de granos de café requeridos por taza, granos de café y tiempo de recarga de agua, etc.

Item key

In discovery rule configuration, select JMX agent in the Type field.

Two item keys are supported for JMX object discovery - jmx.discovery[] and jmx.get[]:

Using jmx.discovery

This item returns a JSON object with low-level discovery macros describing MBean objects or attributes. For example, in the discovery of MBean attributes (reformatted for clarity):

[
           {
               "{#JMXVALUE}":"0",
               "{#JMXTYPE}":"java.lang.Long",
               "{#JMXOBJ}":"java.lang:type=GarbageCollector,name=PS Scavenge",
               "{#JMXDESC}":"java.lang:type=GarbageCollector,name=PS Scavenge,CollectionCount",
               "{#JMXATTR}":"CollectionCount"
           },
           {
               "{#JMXVALUE}":"0",
               "{#JMXTYPE}":"java.lang.Long",
               "{#JMXOBJ}":"java.lang:type=GarbageCollector,name=PS Scavenge",
               "{#JMXDESC}":"java.lang:type=GarbageCollector,name=PS Scavenge,CollectionTime",
               "{#JMXATTR}":"CollectionTime"
           },
           {
               "{#JMXVALUE}":"true",
               "{#JMXTYPE}":"java.lang.Boolean",
               "{#JMXOBJ}":"java.lang:type=GarbageCollector,name=PS Scavenge",
               "{#JMXDESC}":"java.lang:type=GarbageCollector,name=PS Scavenge,Valid",
               "{#JMXATTR}":"Valid"
           },
           {
               "{#JMXVALUE}":"PS Scavenge",
               "{#JMXTYPE}":"java.lang.String",
               "{#JMXOBJ}":"java.lang:type=GarbageCollector,name=PS Scavenge",
               "{#JMXDESC}":"java.lang:type=GarbageCollector,name=PS Scavenge,Name",
               "{#JMXATTR}":"Name"
           },
           {
               "{#JMXVALUE}":"java.lang:type=GarbageCollector,name=PS Scavenge",
               "{#JMXTYPE}":"javax.management.ObjectName",
               "{#JMXOBJ}":"java.lang:type=GarbageCollector,name=PS Scavenge",
               "{#JMXDESC}":"java.lang:type=GarbageCollector,name=PS Scavenge,ObjectName",
               "{#JMXATTR}":"ObjectName"
           }
       ]

In the discovery of MBeans (reformatted for clarity):

[
           {
               "{#JMXDOMAIN}":"java.lang",
               "{#JMXTYPE}":"GarbageCollector",
               "{#JMXOBJ}":"java.lang:type=GarbageCollector,name=PS Scavenge",
               "{#JMXNAME}":"PS Scavenge"
           }
       ]

Macros compatibles

Las siguientes macros son compatibles para su uso en el filtro de la regla de descubrimiento y en prototipos de métricas, iniciadores y gráficos:

Limitations

There are some limitations associated with the algorithm of creating LLD macro names from MBean property names:

• attribute names are changed to uppercase
• attribute names are ignored (no LLD macros are generated) if they consist of unsupported characters for LLD macro names. Supported characters can be described by the following regular expression: A-Z0-9_\.
• if an attribute is called "obj" or "domain" they will be ignored because of the overlap with the values of the reserved Zabbix properties {#JMXOBJ} and {#JMXDOMAIN} (supported since Zabbix 3.4.3.)

Please consider this jmx.discovery (with "beans" mode) example. MBean has the following properties defined:

name=test
       тип=Type
       attributes []=1,2,3
       Name=NameOfTheTest
       domAin=some

As a result of JMX discovery, the following LLD macros will be generated:

• {#JMXDOMAIN} - Zabbix internal, describing the domain of MBean
• {#JMXOBJ} - Zabbix internal, describing MBean object
• {#JMXNAME} - created from "name" property

Ignored properties are:

• тип : its name contains unsupported characters (non-ASCII)
• attributes[] : its name contains unsupported characters (square brackets are not supported)
• Name : it's already defined (name=test)
• domAin : it's a Zabbix reserved name

Ejemplos

Repasemos dos ejemplos prácticos más de creación de reglas LLD con el uso de MBean. Para comprender la diferencia entre una recopilación de reglas LLD MBeans y una regla LLD que recopila mejor los atributos de MBean, por favor eche un vistazo a la siguiente tabla:

Example 1: Discovering Mbeans

This rule will return 3 objects: the top row of the column: MBean1, MBean2, MBean3.

For more information about objects please refer to supported macros table, Discovery of MBeans section.

Discovery rule configuration collecting Mbeans (without the attributes) looks like the following:

The key used here:

jmx.discovery[beans,"*:type=GarbageCollector,name=*"]

All the garbage collectors without attributes will be discovered. As Garbage collectors have the same attribute set, we can use desired attributes in item prototypes the following way:

The keys used here:

jmx[{#JMXOBJ},CollectionCount] 
       jmx[{#JMXOBJ},CollectionTime] 
       jmx[{#JMXOBJ},Valid] 

LLD discovery rule will result in something close to this (items are discovered for two Garbage collectors):

Example 2: Discovering Mbean attributes

This rule will return 9 objects with the following fields: MBean1Attribute1, MBean2Attribute1, Mbean3Attribute1,MBean1Attribute2,MBean2Attribute2, Mbean3Attribute2, MBean1Attribute3, MBean2Attribute3, Mbean3Attribute3.

For more information about objects please refer to supported macros table, Discovery of MBean attributes section.

Discovery rule configuration collecting Mbean attributes looks like the following:

The key used here:

jmx.discovery[attributes,"*:type=GarbageCollector,name=*"]

All the garbage collectors with a single item attribute will be discovered.

In this particular case an item will be created from prototype for every MBean attribute. The main drawback of this configuration is that trigger creation from trigger prototypes is impossible as there is only one item prototype for all attributes. So this setup can be used for data collection, but is not recommended for automatic monitoring.

Usando jmx.get

jmx.get[] es similar a la métrica jmx.discovery[], pero no convierte las propiedades de los objetos Java en nombres de macros de descubrimiento de bajo nivel y por lo tanto, puede devolver valores sin limitaciones que son asociados con la generación de nombres de macros LLD, como guiones o caracteres no ASCII.

Cuando se utiliza jmx.get[] para el descubrimiento, se pueden utilizar macros de descubrimiento de bajo nivel definidas por separado en la pestaña de macro LLD personalizada de la configuración de reglas de descubrimiento, usando JSONPath para apuntar a los valores requeridos.

Descubriendo MBeans

Métrica de descubrimiento: jmx.get[beans,"com.example:type=*,*"]

Respuesta:

[
           {
               "object": "com.example:type=Hello,data-src=data-base,ключ=значение",
               "domain": "com.example",
               "properties": {
                   "data-src": "data-base",
                   "ключ": "значение",
                   "type": "Hello"
               }
           },
           {
               "object": "com.example:type=Atomic",
               "domain": "com.example",
               "properties": {
                   "type": "Atomic"
               }
           }
       ]

Descubriendo atributos de MBean

Métrica de descubrimiento: jmx.get[attributes,"com.example:type=*,*"]

Respuesta:

[
           {
               "object": "com.example:type=*",
               "domain": "com.example",
               "properties": {
                   "type": "Simple"
               }
           },
           {
               "object": "com.zabbix:type=yes,domain=zabbix.com,data-source=/dev/rand,ключ=значение,obj=true",
               "domain": "com.zabbix",
               "properties": {
                   "type": "Hello",
                   "domain": "com.example",
                   "data-source": "/dev/rand",
                   "ключ": "значение",
                   "obj": true
               }
           }
       ]