Monitoring Apache Tomcat
After you install the Instana host agent, the Apache Tomcat sensor is automatically installed and configured. You can view metrics that are related to Apache Tomcat in the Instana UI.
- Supported operating systems
- Supported versions
- Optional configuration
- Metrics collection
Supported operating systems
The supported operating systems of the Tomcat sensor are consistent with host agent requirements, which can be checked in the Supported operating systems section of each host agent, such as Supported operating systems for Unix.
Instana supports monitoring metrics and configuration data for all versions of Apache Tomcat from 5.x to 11.x.
The Apache Tomcat sensor reads the Tomcat configuration file
ServerInfo.properties and extracts the name for the Tomcat instances from it. This name is displayed in the Intana UI.
Optionally, you can change the name of the Tomcat instance within Instana by editing the Tomcat configuration file
To edit the configuration file for renaming the Tomcat instance, complete the following steps:
- Go to the following
- To change the name of the Tomcat instance, modify the value of the
server.infofield. See the following example:
The Apache Tomcat sensor monitors the Apache Tomcat instance and collects the following metrics from it:
To view these metrics, complete the following steps:
- Select Infrastructure in the sidebar of the Instana UI.
- Click a specific monitored host. You can see the host dashboard with all the collected metrics and monitored processes.
The Apache Tomcat sensor collects the following configuration data from the Apache Tomcat instance:
- Web Apps
- Application Configuration
- Data sources
The Apache Tomcat sensor collects the following performance metrics from the Apache Tomcat instance:
|Session count||The number of currently active sessions.||1 second|
|Requests||The number of requests per second.||1 second|
|Average Response Times||The average response time across all requests to a servlet (in milliseconds) per second.||1 second|
|Errors||The number of erroneous requests per second.||1 second|
|Thread count||The number of threads that are currently assigned to a connector.||1 second|
|Busy threads||The number of threads that are currently busy processing requests.||1 second|
|Max threads||The maximum number of threads that a pool can contain.||1 second|
|Connection count||The current number of connections that are handled by an endpoint.||1 second|
|Max connections||The total number of concurrent connections that a server accepts and processes.||1 second|
|Thread count||The current number of threads in a pool.||1 second|
|Queue size||The number of request processing tasks that are currently enqueued in the queue of a thread pool.||1 second|
|Max threads||The maximum number of threads that can be allocated or created in a pool.||1 second|
|Active connections||The current number of active connections that are allocated from a particular data source.||1 second|
|Max connections||The maximum number of active connections that can be allocated at the same time.||1 second|
Each sensor has a curated knowledgebase of health signatures that are evaluated continuously against the incoming metrics. These health signatures are used to raise issues or incidents that depend on user impact.
Built-in events trigger issues or incidents based on failing health signatures on entities. Custom events trigger issues or incidents based on the thresholds of an individual metric of any entity.
For more information about built-events for the Apache Tomcat sensor, see Built-in events reference.
Instana provides tracing support for Apache Tomcat. For more information, see Monitoring Java Virtual Machine.