Monitored technologies · Application servers

Apache Tomcat Monitoring

Health and performance of the server and of every Tomcat webapp, with checks on cache, data sources, sessions and thread pools, without relying on Tomcat’s own tools.

Visibility into servers and webapps

Apache Tomcat is the servlet container used in the official reference implementation of the Java Servlet and JavaServer Pages technologies. It provides a platform for running web applications written in Java and includes the functions of a web server; it is very popular with those looking for a scalable, open source Java application server.

The Sentinet³ Tomcat Pattern provides detailed information on the health and performance of the server and its webapps. IT administrators thus gain visibility into resource consumption both for the server and for each individual webapp, without relying on Tomcat’s own instrumentation.

At a glance
PatternSentinet³ Tomcat Pattern
SourcesServer and webapp metrics, Tomcat logs and configuration
ScopeServer, cache, data sources, sessions, thread pools
Sentinet³ console: detail view of a monitored service with status, check timings and run-time commands
Sentinet³ console: status and detailed parameters of a monitored service.
What it checks

The Pattern’s checks

The Pattern includes 26 checks. Each has configurable thresholds and generates a notification when values exceed them.

Server

CheckWhat it verifies
ReachabilityThe server responds on the network
Port 80Response to HTTP requests
Port 443Response to HTTPS requests
CPUPercentage of CPU utilisation
MemoryMemory usage
DiskFree disk space

Cache

CheckWhat it verifies
Access CountNumber of cache accesses
Cache SizeCache size in MB
Hits CountHit counter

Data Source

CheckWhat it verifies
Num Active (%)Active connections as a percentage
Max ActiveMaximum number of active connections
Max IdleMaximum number of idle connections
Num ActiveNumber of active connections
Num IdleNumber of idle connections

Session

CheckWhat it verifies
Rejected Sessions (%)Rejected sessions as a percentage
Active SessionsNumber of active sessions
Expired SessionsNumber of expired sessions
Max ActiveMaximum number of active sessions
Rejected SessionsNumber of rejected sessions
Session Average Alive TimeAverage session duration
Session CounterNumber of sessions
Session Max Alive TimeMaximum session duration

Thread Pool

CheckWhat it verifies
Current Threads Busy (%)Busy threads as a percentage
Current Thread CountCurrent number of threads
Current Threads BusyNumber of busy threads
Max ThreadsMaximum number of threads
Beyond the metrics

Logs and configuration under control

  • Exceptions in the logs: the Pattern analyses Tomcat’s logs and returns information that helps identify the reported exceptions and generate the corresponding alerts.
  • Configuration changes: Sentinet³ also monitors Tomcat’s configuration: when a change is made, its impact on performance and availability can be measured.
  • Resources per webapp: resource consumption is visible both for the server and for each individual webapp.

Want to see Sentinet³ on your infrastructure?

Tell us about your environment: sites, technologies, critical services. We will show you how Core and Infinity can work on your case.