JVM Uptime Test

This test tracks the uptime of a JVM. Using information provided by this test, administrators can determine whether the JVM was restarted. Comparing uptime across Java applications, an admin can determine the JVMs that have been running without any restarts for the longest time. 

Target of the test : An IBM WebSphere Liberty server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for every Java application monitored

Configurable parameters for the test
Parameter Description

Test period

How often should the test be executed


The host for which the test is to be configured.


The port number at which the specified host listens to


This test can extract metrics from the Java application using either of the following mechanisms:
  • Using SNMP-based access to the Java runtime MIB statistics;
  • By contacting the Service URL of the application via JMX

To configure the test to use SNMP, select the SNMP option. On the other hand, choose the JMX option to configure the test to use JMX instead. By default, the JMX option is chosen here.

Service URL

For the eG agent to collect metrics from the target IBM WebSphere Liberty server, the local connector should be enabled on the target server. Once the connector is enabled, a com.ibm.ws.jmx.local.address file will be created in the ${server.output.dir}/logs/state folder. The eG agent uses this file to connect to the target server and collect the required metrics from it. Therefore, specify the exact path to this file in the Service URL text box. For example, in case of Windows environments, the Service URL Path can be C:\wlp\usr\servers\server1\logs\state and in case of Linux environments, the Service URL Path can be /opt/wlp/ur/servers/server1/logs/state.


Specify the duration (in seconds) for which this test should wait for a response from the target Java application. If there is no response from the target beyond the configured duration, the test will timeout. By default, this is set to 240 seconds.


This parameter appears only if the Mode is set to SNMP. Here specify the port number through which the server exposes its SNMP MIB. Ensure that you specify the same port you configured in the management.properties file in the <JAVA_HOME>\jre\lib\management folder used by the target application. For more details,refer to Enabling SNMP Support for JRE topic.

SNMP Version

This parameter appears only if the Mode is set to SNMP. The default selection in the SNMP version list is v1. However, for this test to work, you have to select SNMP v2 or v3 from this list, depending upon which version of SNMP is in use in the target environment.

SNMP Community

This parameter appears only if the Mode is set to SNMP. Here, specify the SNMP community name that the test uses to communicate with the mail server. The default is public. This parameter is specific to SNMP v1 and v2 only. Therefore, if the SNMP version chosen is v3, then this parameter will not appear.

User name

This parameter appears only when v3 is selected as the SNMP version. SNMP version 3 (SNMPv3) is an extensible SNMP Framework which supplements the SNMPv2 Framework, by additionally supporting message security, access control, and remote SNMP configuration capabilities. To extract performance statistics from the MIB using the highly secure SNMP v3 protocol, the eG agent has to be configured with the required access privileges – in other words, the eG agent should connect to the MIB using the credentials of a user with access permissions to be MIB. Therefore, specify the name of such a user against this parameter. 


This parameter appears only when v3 is selected as the SNMPVERSION. An SNMP context is a collection of management information accessible by an SNMP entity. An item of management information may exist in more than one context and an SNMP entity potentially has access to many contexts. A context is identified by the SNMPEngineID value of the entity hosting the management information (also called a contextEngineID) and a context name that identifies the specific context (also called a contextName). If the User nameprovided is associated with a context name, then the eG agent will be able to poll the MIB and collect metrics only if it is configured with the context name as well. In such cases therefore, specify the context name of the username in the context text box.  By default, this parameter is set to none.


Specify the password that corresponds to the above-mentioned user name. This parameter once again appears only if the snmpversion selected is v3.

Confirm password

Confirm the Authpass by retyping it here


This parameter too appears only if v3 is selected as the SNMPversion. From the AuthType list box, choose the authentication algorithm using which SNMP v3 converts the specified username and password into a 32-bit format to ensure security of SNMP transactions. You can choose between the following options:

  • MD5 - Message Digest Algorithm
  • SHA - Secure Hash Algorithm
  • SHA224 - Secure Hash Algorithm 224 bit
  • SHA256 - Secure Hash Algorithm 256 bit
  • SHA384 - Secure Hash Algorithm 384 bit
  • SHA512 - Secure Hash Algorithm 512 bit


This flag appears only when v3 is selected as the snmpversion. By default, the eG agent does not encrypt SNMP requests. Accordingly, the flag is set to No by default. To ensure that SNMP requests sent by the eG agent are encrypted, select the Yes option. 


If the EncryptFlag is set to Yes, then you will have to mention the encryption type by selecting an option from the EncryptType list. SNMP v3 supports the following encryption types:DES - Data Encryption Standard3DES - Triple Data Encryption StandardAES - Advanced Encryption StandardAES128 - Advanced Encryption Standard 128 bitAES192 - Advanced Encryption Standard 192 bitAES256 - Advanced Encryption Standard 256 bit


Specify the encryption password here.

Confirm password

Confirm the encryption password by retyping it here.


By default, this flag is set to Yes, indicating that, by default, the detailed diagnosis of this test, if enabled, will report the shutdown and reboot times of the server in the manager’s time zone. If this flag is set to No, then the shutdown and reboot times are shown in the time zone of the system where the agent is running i.e., the system being managed for agent-based monitoring.

Data over TCP

This parameter  is applicable only if mode is set to SNMP. By default, in an IT environment, all data transmission occurs over UDP. Some environments however, may be specifically configured to offload a fraction of the data traffic – for instance, certain types of data traffic or traffic pertaining to specific components – to other protocols like TCP, so as to prevent UDP overloads. In such environments, you can instruct the eG agent to conduct the SNMP data traffic related to the monitored target over TCP (and not UDP). For this, set this flag to Yes. By default, this flag is set to No.


This parameter appears only when v3 is selected as the SNMPVersion. Sometimes, the test may not report metrics when AES192 or AES256 is chosen as the Encryption type. To ensure that the test report metrics consistently, administrators need to set this flag to Yes. By default, this parameter is set to No.

DD Frequency

Refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against this parameter.

Detailed Diagnosis

To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option.

The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:

  • The eG manager license should allow the detailed diagnosis capability
  • Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.
Measurements made by the test
Measurement Description Measurement Unit Interpretation

Has JVM been restarted?

Indicates whether or not the JVM has restarted during the last measurement period.


If the value of this measure is No, it indicates that the JVM has not restarted. The value Yes on the other hand implies that the JVM has indeed restarted.

The numeric values that correspond to the restart states discussed above are listed in the table below:

State Value






By default, this measure reports the value Yes or No to indicate whether a JVM has restarted. The graph of this measure however, represents the same using the numeric equivalents – 0 or 1. 

Uptime during the last measure period

Indicates the time period that the JVM has been up since the last time this test ran.


If the JVM has not been restarted during the last measurement period and the agent has been running continuously, this value will be equal to the measurement period. If the JVM was restarted during the last measurement period, this value will be less than the measurement period of the test. For example, if the measurement period is 300 secs, and if the JVM was restarted 120 secs back, this metric will report a value of 120 seconds.  The accuracy of this metric is dependent on the measurement period – the smaller the measurement period, greater the accuracy.

Total Uptime of the JVM

Indicates the total time that the JVM has been up since its last reboot.


Administrators may wish to be alerted if a JVM has been running without a reboot for a very long period. Setting a threshold for this metric allows administrators to determine such conditions.