WebLogic Scripting Tool

Getting Runtime Information

You can use WLST to retrieve information that WebLogic Server instances produce to describe their runtime state. The following sections using WLST to get runtime information:

Accessing Runtime Information: Main Steps

The Administration Server hosts the domain runtime hierarchy which provides access to any MBean on any server in the domain. If the Administration Server is not running for a domain, WLST can connect to individual Managed Servers to retrieve runtime data.

Accessing the runtime information for a domain includes the following main steps:

The following sections provide example scripts for retrieving runtime information about WebLogic Server server instances and domain resources.

Script for Monitoring Server State

The WLST online script in Listing 7-1 navigates the domain runtime hierarchy and checks the status of a Managed Server every 5 seconds. It restarts the server if the server state changes from RUNNING to any other status. It assumes that WLST is connected to the domain’s Administration Server.

For information on how to run this script, see Invoking WLST.

# Node Manager needs to be running to run this script.

import thread
import time

def checkHealth(serverName):
  while 1:
    slBean = getSLCRT(serverName)
    status = slBean.getState()
    print 'Status of Managed Server is '+status
    if status != "RUNNING":
      print 'Starting server '+serverName
      start(serverName, block="true")
    time.sleep(5) 

def getSLCRT(svrName):
    domainRuntime()
    slrBean = cmo.lookupServerLifecycleRuntime(svrName)
    return slcBean

Script for Monitoring the JVM

The WLST online script in Listing 7-2 monitors the HJVMHeapSize for all running servers in a domain; it checks the heap size every 3 minutes and prints a warning if the heap size is greater than a specified threshold. It assumes that the URL for the domain’s Administration Server is t3://localhost:7001.

For information on how to run this script, see Invoking WLST.

waitTime=300000
THRESHOLD=100000000
uname = "weblogic"
pwd = "weblogic"
url = "t3://localhost:7001"
def monitorJVMHeapSize():
    connect(uname, pwd, url)
    while 1:
        serverNames = getRunningServerNames()
        domainRuntime()
        for name in serverNames:
            print 'Now checking '+name.getName()
            try:
           cd("/ServerRuntimes/"+name.getName()+"/JVMRuntime/"+name.getName())
            except WLSTException,e:
                # this typically means the server is not active, just ignore
                pass
            heapSize = cmo.getHeapSizeCurrent()
            if heapSize > THRESHOLD:
            # do whatever is neccessary, send alerts, send email etc
                print 'WARNING: The HEAPSIZE is Greater than the Threshold'
            else:
                print heapSize
        java.lang.Thread.sleep(1800000)

def getRunningServerNames():
    domainConfig()
    return cmo.getServers()

if __name__== "main":
    monitorJVMHeapSize()

Configuring Logging

Using WLST, you can configure a server instance’s logging and message output.

To determine which log attributes can be configured, see LogMBean and LogFileMBean in the WebLogic Server MBean Reference. The reference also indicates valid values for each attribute.

The WLST online script in Listing 7-3 sets attributes of LogMBean (which extends LogFileMBean). For information on how to run this script, see Invoking WLST.

# Connect to the server
connect("weblogic","weblogic","t3://localhost:7001")
edit()
startEdit()

# set CMO to the server log config
cd("Servers/myserver/Log/myserver")
ls ()

# change LogMBean attributes
set("FileCount", 5)
set("FileMinSize", 400)

# list the current directory to confirm the new attribute values
ls ()

# save and activate the changes
save()
activate()

# all done...
exit()

Working with the WebLogic Diagnostics Framework

The WebLogic Diagnostic Framework (WLDF) is a monitoring and diagnostic framework that can collect diagnostic data that servers and applications generate. You configure WLDF to collect the data and store it in various sources, including log records, data events, and harvested metrics. For more information, see Configuring and Using the WebLogic Diagnostics Framework.

For example scripts that demonstrate using WLST to configure the WebLogic Diagnostic Framework, see “ WebLogic Scripting Tool Examples” in Configuring and Using the WebLogic Diagnostics Framework.

To view the collected diagnostics information using WLST, use one of the following commands to export the data from the WLDF repositories: