JMX

Apache ActiveMQ has extensive support for JMX to allow you to monitor and control the behavior of the broker via the JMX MBeans.

Using JMX to monitor Apache ActiveMQ

You can enable/disable JMX support as follows...

1. Run a broker setting the broker property useJmx to true. (From 4.0 onwards this is enabled by default)
i.e.

For xbean configuration

<broker useJmx="true" brokerName="BROKER1">
...
</broker>

For url configuration

broker:(tcp://localhost:61616)?useJmx=true

2. Run a JMX console (e.g. jconsole - JMX console included in the JDK <JAVA_HOME>/bin/jconsole.exe)

3. Connect to the given JMX URL:

The ActiveMQ broker should appear in the list of local connections, if you are running JConsole on the same host as ActiveMQ.

To connect to a remote ActiveMQ instance, or if the local process does not show up, use Remote Process option, and enter an URL. Here is an example localhost URL:

service:jmx:rmi:///jndi/rmi://localhost:1099/jmxrmi

Using the Apache ActiveMQ version on OS X it appears as follows:


 

ActiveMQ MBeans Reference

For additional references provided below is a brief hierarchy of the mbeans and a listing of the properties, attributes, and operations of each mbeans.

 bean Type Properties / ObjectName  Attributes  Operations 
 roker

* Type=Broker

  • BrokerName=<broker identifier>

* BrokerId

  • TotalEnqueueCount

  • TotalDequeueCount

  • TotalConsumerCount

  • TotalMessages

  • TotalMessagesCached

  • MemoryLimit

  • MemoryPercentageUsed

* start

  • stop

  • terminateJVM

  • resetStatistics

  • gc
 estination

* Type=Queue|Topic

  • Destination=<destination identifier>

  • BrokerName=<name of broker>

* EnqueueCount

  • DequeueCount

  • ConsumerCount

  • Messages

  • MessagesCached

* resetStatistics

  • gc
 etworkConnector

* Type=NetworkConnector

  • BrokerName=<name of broker>

* start

  • stop
 onnector

* Type=Connector

  • ConnectorName=<connector identifier>

  • BrokerName=<name of broker>

* EnqueueCount

  • DequeueCount

* start

  • stop

  • resetStatistics
 onnection

* Type=Connection

  • Connection=<connection identifier>

  • BrokerName=<name of broker>

* EnqueueCount

  • DequeueCount

  • DispatchQueueSize

  • Active

  • Blocked

  • Connected

  • Slow

* start

  • stop

  • resetStatistics

Command line utilities are also available to let you monitor ActiveMQ. Refer to ActiveMQ Command Line Tools Reference for usage information.

Password Protecting the JMX Connector

(For Java 1.5+)

1. Make sure JMX is enabled, but tell ActiveMQ not create its own connector so that it will use the default JVM JMX connector.

<broker xmlns="http://activemq.org/config/1.0" brokerName="localhost"useJmx="true">

  ...

  <managementContext>
     <managementContext createConnector="false"/>
  </managementContext>

  ...

</broker>

2. Create access and password files

conf/jmx.access:

# The "monitorRole" role has readonly access.
# The "controlRole" role has readwrite access.
monitorRole readonly
controlRole readwrite

conf/jmx.password:

# The "monitorRole" role has password "abc123".
# The "controlRole" role has password "abcd1234".
monitorRole abc123
controlRole abcd1234

(Make sure both files are not world readable - more info can be find here to protect files)

For more details you can see the Monitoring Tomcat Document

3. Modify the "activemq" startup script (in bin) to enable the Java 1.5+ JMX connector

Find the "SUNJMX=" line and change it too:

1. Windows

  SUNJMX=-Dcom.sun.management.jmxremote.port=1616 -Dcom.sun.management.jmxremote.ssl=false \
    -Dcom.sun.management.jmxremote.password.file=%ACTIVEMQ_BASE%/conf/jmx.password \
    -Dcom.sun.management.jmxremote.access.file=%ACTIVEMQ_BASE%/conf/jmx.access

2. Unix

  SUNJMX="-Dcom.sun.management.jmxremote.port=1616 -Dcom.sun.management.jmxremote.ssl=false \
    -Dcom.sun.management.jmxremote.password.file=${ACTIVEMQ_BASE}/conf/jmx.password \
    -Dcom.sun.management.jmxremote.access.file=${ACTIVEMQ_BASE}/conf/jmx.access"

This could be set in /etc/activemq.conf instead (if you have root access):

1. Windows

ACTIVEMQ_HOME=DRIVE_LETTER:/where/ActiveMQ/is/installed
ACTIVEMQ_BASE=%ACTIVEMQ_HOME%
SUNJMX=-Dcom.sun.management.jmxremote.port=1616 -Dcom.sun.management.jmxremote.ssl=false \
    -Dcom.sun.management.jmxremote.password.file=%ACTIVEMQ_BASE%/conf/jmx.password \
    -Dcom.sun.management.jmxremote.access.file=%ACTIVEMQ_BASE%/conf/jmx.access

2. Unix

ACTIVEMQ_HOME=DRIVE_LETTER:/where/ActiveMQ/is/installed
ACTIVEMQ_BASE=${ACTIVEMQ_HOME}
SUNJMX="-Dcom.sun.management.jmxremote.port=1616 -Dcom.sun.management.jmxremote.ssl=false \
    -Dcom.sun.management.jmxremote.password.file=${ACTIVEMQ_BASE}/conf/jmx.password \
    -Dcom.sun.management.jmxremote.access.file=${ACTIVEMQ_BASE}/conf/jmx.access"

4. Start ActiveMQ

You should be able to connect to JMX on the JMX URL

service:jmx:rmi:///jndi/rmi://<your hostname>:1616/jmxrmi

And you will be forced to login.

Advanced JMX Configuration

The activemq.xml configuration file allows you to configure how ActiveMQ is exposed to JMX for management. In some cases, you may need to tweak some of it's settings such as what port is used.

Example:

<broker useJmx="true">
	<managementContext>
	   <managementContext connectorPort="2011" jmxDomainName="test.domain"/>
	</managementContext>
</broker>

In 4.0.1 or later, on Java 1.5 or later we try and use the default platform MBeanServer (so that things like the JVM threads & memory settings are visible).

If you wish to change the Java 5 JMX settings you can use various JMX system properties

For example you can enable remote JMX connections to the Sun JMX connector, via setting the following environment variable (using set or export depending on your platform). These settings only configure the Sun JMX connector within Java 1.5+, not the JMX connector that ActiveMQ creates by default.

SUNJMX=-Dcom.sun.management.jmxremote=true -Dcom.sun.management.jmxremote.port=1616 \
-Dcom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.ssl=false

(The SUNJMX environment variable is simple used by the "activemq" startup script, as additional startup parameters for java. If you start ActiveMQ directly, you'll have to pass these parameters yourself.)

ManagementContext Properties Reference

Property Name Default Value Description
useMBeanServer true If true then it avoids creating a new MBean server if a MBeanServer has already been created in the JVM
jmxDomainName org.apache.activemq The jmx domain that all objects names will use
createMBeanServer true If we should create the MBeanServer is none is found.
createConnector true If we should create a JMX connector (to allow remote management) for the MBeanServer
connectorPort 1099 The port that the JMX connector will use
connectorHost localhost The host that the JMX connector and RMI server (if rmiServerPort>0) will use
rmiServerPort 0 The RMI server port, handy if port usage needs to be restricted behind a firewall
connectorPath /jmxrmi The path that JMX connector will be registered under
findTigerMBeanServer true Enables/disables the searching for the Java 5 platform MBeanServer