JMX-Based Monitoring
Java Management Extensions (JMX) is a technology that lets you implement management interfaces for Java applications. A management interface, as defined by JMX, is composed of named objects called MBeans (Management Beans). MBeans are registered with a name (an ObjectName) in an MBeanServer. To manage a resource or many resources in your application, write an MBean that defines its management interface. Then register that MBean in your MBeanServer. The content of the MBeanServer can then be exposed through various protocols, implemented by protocol connectors, or protocol adaptors.
JMX is enabled in WSO2 Carbon by default. Therefore, the WSO2 Data Services Server facilitates JMX-based monitoring. Some of the monitoring and management capabilities available in the DSS management console are also exposed via JMX.
You can change the JMX configuration by editing the jmx.xml
file, which is inside <DSS_HOME>/repository/conf/etc
directory. You can configure JMX ports, RMIRegistryPort and RMIServerPort from the "Ports" section of the carbon.xml
, which is in <DSS_HOME>/repository/conf
directory.
<JMX> <!--The port RMI registry is exposed--> <RMIRegistryPort>9999</RMIRegistryPort> <!--The port RMI server should be exposed--> <RMIServerPort>11111</RMIServerPort> </JMX>
If JMX is enabled, when the server starts up, it will print the JMX Server URL on the console as follows.
INFO {org.wso2.carbon.core.init.CarbonServerManager} - JMX Service URL : service:jmx:rmi://<your-ip>:11111/jndi/rmi://<your-ip>:9999/jmxrmi
Using 'jconsole' to manage and monitor WSO2 DSS
Jconsole is a JMX-compliant monitoring tool. It comes with the Jave Development Kit (JDK) 1.5 and newer versions and can be found in <JDK_HOME>/bin/
directory. For information on installing JDK, refer to Installing JDK on Windows, Linux or Solaris.
You can start the tool by simply typing jconsole in a command (shell) prompt from <JDK_HOME>/bin.
Once the console is opened, you can connect to Carbon by providing the following URL as the Remote Process URL. You can type in the default username and password combination admin/admin to log in. Note that this is the same administrator account that is used to log into the DSS management console. Any user having the admin role can log in to JMX.
The "Java Monitoring & Management Console" opens. The first window you see looks similar to the following:
Go to the "MBeans" tab to see the "org.wso2.carbon" domain, which contains some MBeans as follows:
The ServerAdmin MBean
The ServerAdmin MBean is used for administering the DSS instance.
There are several server attributes such as "ServerStatus", "ServerData" and "ServerVersion". The "ServerStatus" attribute can take any of the following values:
- RUNNING
- SHUTTING_DOWN
- RESTARTING
- IN_MAINTENANCE
The ServerAdmin MBean has the following operations:
- shutdown - forcefully shutdown the server
- restart - forcefully restart the server
- restartGracefully - wait till all current requests are served and then restart
- shutdownGracefully - wait till all current requests are served and then shutdown
- startMaintenance - switch the server to maintenance mode. No new requests will be accepted while the server is in maintenance
- endMaintenance - switch the server to normal mode, if it was switched to maintenance mode earlier.
The ServiceAdmin MBean
The ServiceAdmin MBean is used for administering services deployed in DSS. Its attributes are as follows:
- NumberOfActiveServices - The number of services which can currently serve requests.
- NumberOfInactiveServices - The number of services which have been disabled by an administrator.
- NumberOfFaultyServices - The number of services which are faulty.
operations available in the ServiceAdmin MBean:
- startService(p1:string) - The p1 parameter is the service name. You can activate a service using this operation.
- stopService(p1:string) - The p1 parameter is the service name. You can deactivate/disable a service using this operation.
The Statistics MBean
The Statistics MBean is used for monitoring system and server statistics. Its attributes are as follows:
- AvgSystemResponseTime - The average response time for all the services deployed in the system. The beginning of the measurement is the time at which the server started.
- MaxSystemResponseTime - The maximum response time for all the services deployed in the system. The beginning of the measurement is the time at which the server started.
- MinSystemResponseTime - The minimum time for all the services deployed in the system. The beginning of the measurement is the time at which the server started.
- SystemFaultCount - The total number of faults that occurred in the system since the server was started.
- SystemRequestCount - The total number of requests that has been served by the system since the server was started.
- SystemResponseCount - The total number of response that has been sent by the system since the server was started.
Operations available in the Statistics MBean:
- getServiceRequestCount(p1:string) - The p1 parameter is the service name. You can get the total number of requests received by this service since the time it was deployed, using this operation.
- getServiceResponseCount(p1:string) - The p1 parameter is the service name. You can get the total number of responses sent by this service since the time it was deployed, using this operation.
- getServiceFaultCount(p1:string) - The p1 parameter is the service name. You can get the total number of fault responses sent by this service since the time it was deployed, using this operation.
- getMaxServiceResponseTime(p1:string) - The p1 parameter is the service name. You can get the maximum response time of this service since deployment.
- getMinServiceResponseTime(p1:string) - The p1 parameter is the service name. You can get the minimum response time of this service since deployment.
- getAvgServiceResponseTime(p1:string) - The p1 parameter is the service name. You can get the average response time of this service since deployment.
- getOperationRequestCount(p1:string, p2:string) - The p1 parameter is the service name. The p2 parameter is the operation name. You can get the total number of requests received by this operation since the time its service was deployed, using this operation.
- getOperationResponseCount(p1:string, p2:string) - The p1 parameter is the service name. The p2 parameter is the operation name. You can get the total number of responses sent by this operation since the time its service was deployed, using this operation.
- getOperationFaultCount(p1:string, p2:string) - The p1 parameter is the service name. The p2 parameter is the operation name. You can get the total number of fault responses sent by this operation since the time its service was deployed, using this operation.
- getMaxOperationResponseTime(p1:string, p2:string) - The p1 parameter is the service name. The p2 parameter is the operation name. You can get the maximum response time of this operation since deployment.
- getMinOperationResponseTime(p1:string, p2:string) - The p1 parameter is the service name. The p2 parameter is the operation name. You can get the minimum response time of this operation since deployment.
- getAvgOperationResponseTime(p1:string, p2:string) - The p1 parameter is the service name. The p2 parameter is the operation name. You can get the average response time of this operation since deployment.