Apache Tomcat

Apache Tomcat, often referred to as Tomcat Server, is an open-source Java Servlet Container developed by the Apache Software Foundation (ASF). Tomcat implements several Java EE specifications including Java Servlet, JavaServer Pages (JSP), Java EL, and WebSocket, and provides a “pure Java” HTTP web server environment in which Java code can run.

Tomcat is developed and maintained by an open community of developers under the auspices of the Apache Software Foundation, released under the Apache License 2.0 license, and is open-source software.

Prerequisites

For standard installation of Tomcat (extracting the tar), add the following in the ~/.bashrc file:

export JAVA_HOME=/usr/lib/jvm/java-1.11.0-openjdk-amd64  #add this line where jvm is installed on the machine
export export CATALINA_HOME=/opt/tomcat/apache-tomcat-7.0.105  #add this line where the extracted directory is present

Create a file setenv.sh, add the following lines, and execute the file before you start the Tomcat server:

CATALINA_OPTS="-Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=7199 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=false"

For Virtual Machines, install the Linux Agent.

Configuring the credentials

Configure the credentials in the directory /opt/opsramp/agent/conf/app.d/creds.yaml

tomcat:
- name: tomcat
  user: <username>
  pwd: <Password>
  encoding-type: plain
  labels:
    key1: val1
    key2: val2

Configuring the application

Virtual machine

Configure the application in the directory /opt/opsramp/agent/conf/app/discovery/auto-detection.yaml

- name: tomcat
  instance-checks:
    process-check:
      - tomcat
    port-check:
      - 8080
  mon-type: "jmx"
  misc:
    jmx-port: "7199"

Docker environment

Configure the application in the directory /opt/opsramp/agent/conf/app/discovery/auto-container-detection.yaml

- name: tomcat
  container-checks:
    image-check:
      - tomcat
    port-check:
      - 8080
  mon-type: "jmx"
  misc:
    jmx-port: "7199"

Kubernetes environment

Configure the application in config.yaml

- name: tomcat
  container-checks:
    image-check:
      - tomcat
    port-check:
      - 8080
  mon-type: "jmx"
  misc:
    jmx-port: "7199"

Validate

Go to Resources under the Infrastructure tab to check if your resources are onboarded and the metrics are collected.

Metrics


OpsRamp Metric	Metric Display Name	Unit	Description
tomcat_maxThreads	Max Threads	threads	Maximun Number of threads created
tomcat_currentThreadCount	Current Thread Count	threads	Number of threads currently active
tomcat_currentThreadsBusy	Current Threads Busy	threads	Number of busy threads
tomcat_jspCount	Jsp Count		Number of times JSPs were accessed on all the applications
tomcat_jspReloadCount	Jsp Reload Count		Number of times JSPs were reloaded on all the applications
tomcat_Servlet_requestCount	Servlet Requestcount	Requests	Number of requests served by the servlet
tomcat_Servlet_errorCount	Servlet Errorcount	Errors	Number of erroneous requests received by the servlet
tomcat_Servlet_processingTime	Servlet Processingtime	Processing Time	Amount of processing time taken
tomcat_bytesSent	Bytes Sent	megabytes	Megabytes sent by all the request processors running on the Apache Tomcat
tomcat_bytesReceived	Bytes Received	megabytes	Megabytes received by all the request processors running on the Apache Tomcat
tomcat_errorCount	Error Count	Errors	Errors on all the request processors running on the Apache Tomcat
tomcat_requestCount	Request Count	Requests	Requests on all the request processors running on the Apache Tomcat
tomcat_maxTime	Max Time	milliseconds	The longest request processing time in milliseconds
tomcat_processingTime	Processingtime	Processing Time	Amount of processing time taken
tomcat_jvm_HeapMemoryUsage_commited	Jvm Heap Memory Usage Commited	megabytes	Heap memory committed in MB for the server
tomcat_jvm_HeapMemoryUsage_used	Jvm Heap Memory Usage Used	megabytes	Heap memory usage in MB of the server
tomcat_jvm_NonHeapMemoryUsage_commited	Jvm Non Heap Memory Usage Commited	megabytes	Non heap memory committed in MB for the server
tomcat_jvm_NonHeapMemoryUsage_used	Jvm Non Heap Memory Usage Used	megabytes	Non heap memory usage in MB of the server
tomcat_jvm_OpenFileDescriptorCount	Jvm Open File Descriptor Count	Open FDs	Number of Open file descriptors of the server
tomcat_jvm_ThreadCount	Jvm Threadcount	threads	Number of threads
tomcat_jvm_Uptime	Jvm Uptime	Minutes	Uptime of the server
tomcat_Cache_accessCount	Cache Accesscount	Accesses	Number of times the cache was accessed
tomcat_cache_hitsCount	Cache Hitscount	Hits	Number of times the cache was hit
tomcat_StringCache_hitsCount	String Cache Hitscount	Accesses	The number of string cache hits
tomcat_StringCache_accessCount	String Cache Accesscount	Hits	The number of accesses to the string cache
tomcat_activeSessions	Active Sessions	Sessions	Number of active sessions to the server