This is an Enterprise Plugin which allow you to monitor Tomcat web servers using mod_status. For more information visit the following webpage: http://pandorafms.com/index.php?sec=Library&sec2=repository&lng=en&action=view_PUI&id_PUI=275

1. Pandora FMS
Administrator Manual
Apache Tomcat Plugin

2. Administrator Manual Apache Tomcat Plugin
© Artica Soluciones Tecnológicas 2005­2012
Index
1Changelog...........................................................................................................................................3
2Introduction........................................................................................................................................4
3Compatibility Matrix..........................................................................................................................5
4Documentation provided by the requesting area................................................................................6
5Modules avalible with Tomcat plugin................................................................................................7
6Using and plugin configuration..........................................................................................................8
6.1.Plugin Agent (local) ..................................................................................................................8
6.2.SNMP Monitoring...................................................................................................................10
6.3. JMX Monitoring.....................................................................................................................11

3. 1 CHANGELOG
Date Author Change Version
09/05/12 Tomas First Version v1r1
21/12/12 Tomas Bug fixed v1r2
14/01/12 Tomas Bug fixed v1r3
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4. 2 INTRODUCTION
Taking as an starting point that we have installed both Pandora and the Apache Tomcat server, we
are going to explain how to get information about the status of the server and the applications that
run on it.
There are different methods to reach our target, from using agent plugins for including the
modules that monitor this information offered by web pages in the Pandora server, to the use of
SNMP and programs that are dedicated to this objective, like JMX through jconsole:
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5. 3 COMPATIBILITY MATRIX
Systems where it has been tested • Tomcat 6.0.35
Systems where it should work • Tomcat 6.x and higher
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6. 4 DOCUMENTATION PROVIDED BY THE REQUESTING AREA
The documentation provided by the area which requests the monitoring services is:
• Username: username to authenticate into Tomcat
• Password: password to authenticate into Tomcat
• Tomcat server IP: IP address of Tomcat server which will be monitored.
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7. 5 MODULES AVALIBLE WITH TOMCAT PLUGIN
The modules returned by this plugin are:
• ConnectorName:JK_THREADS_BUSY
• ConnectorName:JK_THREAD_COUNT
• ConnectorName:JK_MAX_THREADS
• TOMCAT_FREE_MEM
• TOMCAT_MAX_MEM
• TOMCAT_TOTAL_MEM
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8. 6 USING AND PLUGIN CONFIGURATION
6.1. Plugin Agent (local)
In this example we suppose that we have installed the Pandora server and the Tomcat server in
different machines, with all the monitoring programs correctly installed (Pandora Agent, JMX con
jconsole)
We need an script that gets information from the XML page that contains the Apache Tomcat data
In our case we use a Turnkey Apache Tomcat, in which that page is at:
http://<Tomcat-IP-Address>:<Port>/manager/status?XML=true
Note: by default Tomcat port is 8080
This script is going to store this page in a temporary file and is going to get the corresponding
values for each data that we want to monitor and present it in an XML format ready to be
introduced in Pandora.
The plugin only works with Tomcat servers with two or more connectors defined so its very
important to define at least two connectors to ensure the plugin works properly.
/etc/tomcat<version>/server.xml
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9. The script is the following:
pandora_tomcat.pl
Once that we have the script with the values that we want to monitor, we include it in the
pandora_agent.conf as an agent plugin. This plugin will introduce one module for each of these
values, visible in the Pandora server web interface.
Note: It is very importan to change plugin file permissions to ensure the server can execute it.
Responding to the inclusion of new connectors in the Tomcat server, the program will answer
adding new modules in a dynamic way with information about each new connector.
The Java connectors are APIs that gives an interface between one Java program and other
applications or servers. Those connectors makes to show to the Java program the other server or
application as an Enterprise JavaBean (EJB), providing compatibility between both of them.
This way, each module will be identified by connector name plus the kind of data that it collects.
/etc/pandora/pandora_agent.conf
module_plugin <ruta­plugin> ­­user=username ­–password=userpass
http://<TomcatServer­IP­Address>:<Port>/manager/status?XML=true <plugin­name>
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10. 6.2. SNMP Monitoring
You can use one of the serveral SNMP­JMX adaptors to monitor Apache Tomcat.
Between them, the most important are:
– Westhawk SNMP
– Sun JDMK
Each one with their corresponding configurations allow us to convert the JMX notifications in SNMP
Traps and extract the information about the server status.
Now, we only have to introduce the OIDs of the MIBs generated by the adaptor with their
corresponding value and kind of data in the Pandora server, and it will be ready to be monitored.
Other way to monitor it is by using JMX.
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11. 6.3. JMX Monitoring
JMX (Java Management Extensions) offers the tools to implement solutions that are distributed,
modular, dynamic , and that are web base to manage and monitor devices, applications and
networks controlled by services, specialized for Java .
JMX uses a HTTP adaptor to show the information that it manages in the web
We can take advantage of the extraction that the HTTP adaptor gets form the data parsing the in an
XML format that is compatible with Pandora.
Anyway, it is better to use the other two methods and leave the last option just as other choice.
There is an easier way to monitor the Tomcat server using JMX, if we use the twiddle command, a
JMX client that works collecting the different data from the server Mbeans, in a format <name­
data>=<data> once it is executed. With it we can collect informtation of the Mbeans features that
contains the information about the status of the system and the connectors.
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