Documentation forHybrid Cloud Observability Essentialsand Server & Application Monitor

Tomcat Server Monitors

Apache Tomcat is a Java servlet container that runs on JVMs. In SAM, a Tomcat Server Monitor is a type of component monitor that can be used in the Tomcat Server or custom templates. For example, the Tomcat Free Memory component monitor collects the amount of heap space currently available to a JVM. template.

A Tomcat Server Monitor uses HTTP requests such as http://{$IP}:{$PORT}/manager/status/?XML=true to collect data from target servers. Responses are expected in XML format.

Server configuration

Configure Java application servers and JVMs for SAM monitoring.

If you encounter issues with AIX systems, enable remote access in the following Tomcat configuration file: conf/Catalina/localhost/manager.xml

To use the Orion Platform Agent for Linux instead of agentless SNMP polling, see Configure Linux/Unix systems for monitoring by the Orion Platform agent in SAM.

Statistic

The variable specified in the Tomcat Variables Name field.

Free Memory

Amount of heap space currently available to the JVM.

Total Memory

Total memory currently allocated to the JVM heap space.

Max Memory

Maximum size of the heap space not including the permanent generation area.

Total Processing Time

Total processing time in milliseconds since server start.

Total Request Count

Total requests from server since server start.

Total Bytes Sent

Total bytes sent from server since server start.

Total Bytes Received

Total bytes sent to server since server start.

Total Error Count

Total error count from all request processors.

Field descriptions

Description

A default description of the monitor. You can override the default description by adding to or replacing the text, which will then be automatically saved. The variable to access this field is ${UserDescription}.

Enable Component

Determines if the component is enabled. Disabling the component leaves it in the application in a deactivated state that doesn't influence SAM application availability or status.

Credential for Monitoring

Provide Tomcat credentials for a user associated with the Manager role, as configured in the tomcat-users.xml file on target JVMs. Here is an example:

<role rolename="manager"/> <user username="user" password="pass" roles="manager"/>

Port Number

Specify the port number used by the web site. The default port is 8080.

Url

Specify the URL you want to monitor. The ${IP} and ${PORT} variables in the default value for this field attempt to monitor a web site at the IP address of the assigned node.

Ignore CA Errors

Specify if the component monitor should ignore the certificate authority (CA) errors. If this setting is disabled, users will be prompted to verify untrusted connections before proceeding.

Ignore CN Errors

Specify if the component monitor should ignore Common Name (CN) errors. If this setting is disabled, users will be prompted to verify untrusted connections before proceeding.

Ignore CN Errors

Specify if the component monitor should ignore Certificate Revocation List (CRL) errors. If this setting is disabled, users will be prompted to verify untrusted connections before proceeding.

Tomcat Variables Name

Specify the Tomcat server variable to be monitored.

Convert Value

Select the "Yes, convert returned value" option to display fields where you can select a common function or enter a custom formula. The Custom Conversion option provides basic arithmetic operators (+, -, *, /), plus built-in mathematical functions for more advanced conversions. See Convert values in data transformations for SAM component monitors.

Response Time Threshold

Set warning and critical threshold conditions based on response time. The response time is the time in milliseconds it takes SAM to determine that a component is not Down and to retrieve any statistical data. See Application Monitor Thresholds for details.

Statistic Threshold

Specify when a threshold that indicates a warning or critical level has been breached. Logical operators are in the drop down followed by a blank field for you to enter the value of this threshold. For example: Less than 15 for warning, Less than 5 for critical. See Application Monitor Thresholds for details.

User Notes

Add notes for easy reference. You can access this field by using the variable, ${UserNotes}.

Troubleshoot Tomcat

To check XML responses from a Tomcat server, send a simple HTTP request through any web browser to check for raw XML content. Use the following format: http://host:port/manager/status/?XML=true

You can also query your Tomcat server through CLI using wget.