(dist)(iseries)

Limiting the growth of JVM log files

We can use scripting to configure the size of JVM log files. JVM logs record events or information from a running JVM.

There are two ways to perform this task. This topic demonstrates how to use the AdminConfig object to modify the server configuration. Alternatively, we can use the configureJavaProcessLogs Jython script in the AdminServerManagement script library to configure the JVM log settings. The wsadmin tool automatically loads the script when the tool starts. Use the following syntax to configure JVM log settings using the configureJavaProcessLogs script:

AdminServerManagement.configureJavaProcessLogs(nodeName, serverName, processLogRoot, otherAttributeList)

For additional information and argument definitions, see the documentation for the AdminServerMananagment script library.

1. Start the wsadmin scripting tool.
   

2. Identify the application server of interest.

   Determine the configuration ID of the application server of interest and assign it to the server1 variable:

   • Jacl:
     set s1 [$AdminConfig getid /Cell:mycell/Node:mynode/Server:server1/]

   • Jython:

     s1 = AdminConfig.getid('/Cell:mycell/Node:mynode/Server:server1/')
     print s1

     where:

     Element	Description
     set	is a Jacl command
     s1	is a variable name
     $	is a Jacl operator for substituting a variable name with its value
     AdminConfig	is an object representing the WAS configuration
     getid	is an AdminConfig command
     Cell	is the object type
     mycell	is the name of the object that will be modified
     Node	is the object type
     mynode	is the name of the object that will be modified
     Server	is the object type
     server1	is the name of the object that will be modified
     print	a Jython command

   Example output:

   server1(cells/mycell/nodes/mynode/servers/server1|server.xml#Server_1)

3. Identify the stream log of interest.

   Determine the stream log of interest and assign it to the log variable. The following example identifies the output stream log:

   • Jacl:
     set log [$AdminConfig showAttribute $s1 outputStreamRedirect]

   • Jython:
     log = AdminConfig.showAttribute(s1, 'outputStreamRedirect')

   The following example identifies the error stream log:

   • Jacl:
     set log [$AdminConfig showAttribute $s1 errorStreamRedirect]

   • Jython:
     log = AdminConfig.showAttribute(s1, 'errorStreamRedirect')

   Example output:

   (cells/mycell/nodes/mynode/servers/server1|server.xml#StreamRedirect_2)

4. List the current values of the stream log.

   Use the following example to display the current values of the stream log of interest:

   • Jacl:
     $AdminConfig show $log

   • Jython:
     AdminConfig.show(log)

   Example output:

   {baseHour 24}
   {fileName ${SERVER_LOG_ROOT}/SystemOut.log}
   {formatWrites true}
   {maxNumberOfBackupFiles 1}
   {messageFormatKind BASIC}
   {rolloverPeriod 24}
   {rolloverSize 1}
   {rolloverType SIZE}
   {suppressStackTrace false}
   {suppressWrites false}

5. Modify the rotation policy for the stream log.

   The following example sets the rotation log file size to two megabytes:

   • Jacl:
     $AdminConfig modify $log {{rolloverSize 2}}

   • Jython:
     AdminConfig.modify(log, [['rolloverSize', 2]])

   The following example sets the rotation policy to manage itself. It is based on the age of the file with the rollover algorithm loaded at midnight, and the log file rolling over every 12 hours:

   • Jacl:
     $AdminConfig modify $log {{rolloverType TIME} {rolloverPeriod 12} {baseHour 24}}

   • Jython:
     AdminConfig.modify(log, [['rolloverType', 'TIME'], ['rolloverPeriod', 12], ['baseHour', 24]])

   The following example sets the log file to roll over based on both time and size:

   • Jacl:
     $AdminConfig modify $log {{rolloverType BOTH} {rolloverSize 2} {rolloverPeriod 12} {baseHour 24}}

   • Jython:
     AdminConfig.modify(log, [['rolloverType', 'BOTH'], ['rolloverSize', 2], ['rolloverPeriod', 12], ['baseHour', 24]])

6. Save the configuration changes.

   Use the following command example to save the configuration changes:

   AdminConfig.save()

7. In a network deployment environment only, synchronize the node.

   Use the syncActiveNode or syncNode scripts in the AdminNodeManagement script library to propagate the configuration changes to node or nodes.

   • Use the syncActiveNodes script to propagate the changes to each node in the cell:
     AdminNodeManagement.syncActiveNodes()

   • Use the syncNode script to propagate the changes to a specific node:
     AdminNodeManagement.syncNode("myNode")

Related tasks

Configure the JVM logs

Use the wsadmin scripting AdminConfig object for scripted administration

Server settings configuration scripts

JVM log settings

Commands for the AdminConfig object