---
title: Apache Tomcat
slug: apache-tomcat
docTags: 
createdAt: 2025-01-25T19:03:24.997Z
---

OpsVerse ObserveNow can pull logs and metrics from Apache Tomcat using the **[jmx\_exporter](https://github.com/prometheus/jmx_exporter/)** that can be configured using the OpsVerse Agent. Please follow the steps below to configure the agent to monitor your Tomcat installation

:::hint{type="info"}
**Prerequisite**: OpsVerse ObserveNow Agent installed on the VM running Tomcat following the steps [mentioned here](https://docs.opsverse.io/install-the-opsverse-agent#dszlx)
:::

Assuming you have the ObserveNow agent up and running on the VM, you can follow the nest steps to configure Tomcat observability

# Metrics

## Install the JMX Exporter

```bash
# for amd64
curl https://raw.githubusercontent.com/OpsVerseIO/installers/main/prometheus-exporters/install-exporter-amd64.sh | sudo bash -s -- -e jmx  

# for arm64
curl https://raw.githubusercontent.com/OpsVerseIO/installers/main/prometheus-exporters/install-exporter-arm64.sh | sudo bash -s -- -e jmx  
```

## Configure JMX Exporter for Tomcat

Open `/etc/opsverse/exporters/jmx/config.yaml` and add the following config into it:

```yaml
lowercaseOutputLabelNames: true
lowercaseOutputName: true
whitelistObjectNames: ["java.lang:type=OperatingSystem", "Catalina:*"]
blacklistObjectNames: []
rules:
  - pattern: 'Catalina<type=Server><>serverInfo: (.+)'
    name: tomcat_serverinfo
    value: 1
    labels:
      serverInfo: "$1"
    type: COUNTER
  - pattern: 'Catalina<type=GlobalRequestProcessor, name=\"(\w+-\w+)-(\d+)\"><>(\w+):'
    name: tomcat_$3_total
    labels:
      port: "$2"
      protocol: "$1"
    help: Tomcat global $3
    type: COUNTER
  - pattern: 'Catalina<j2eeType=Servlet, WebModule=//([-a-zA-Z0-9+&@#/%?=~_|!:.,;]*[-a-zA-Z0-9+&@#/%=~_|]), name=([-a-zA-Z0-9+/$%~_-|!.]*), J2EEApplication=none, J2EEServer=none><>(requestCount|processingTime|errorCount):'
    name: tomcat_servlet_$3_total
    labels:
      module: "$1"
      servlet: "$2"
    help: Tomcat servlet $3 total
    type: COUNTER
  - pattern: 'Catalina<type=ThreadPool, name="(\w+-\w+)-(\d+)"><>(currentThreadCount|currentThreadsBusy|keepAliveCount|connectionCount|acceptCount|acceptorThreadCount|pollerThreadCount|maxThreads|minSpareThreads):'
    name: tomcat_threadpool_$3
    labels:
      port: "$2"
      protocol: "$1"
    help: Tomcat threadpool $3
    type: GAUGE
  - pattern: 'Catalina<type=Manager, host=([-a-zA-Z0-9+&@#/%?=~_|!:.,;]*[-a-zA-Z0-9+&@#/%=~_|]), context=([-a-zA-Z0-9+/$%~_-|!.]*)><>(processingTime|sessionCounter|rejectedSessions|expiredSessions):'
    name: tomcat_session_$3_total
    labels:
      context: "$2"
      host: "$1"
    help: Tomcat session $3 total
    type: COUNTER
```

## Configure Tomcat to use JMX Exporter

In the same directory where `catalina.sh` is, create a file named `setenv.sh` (*usually `/opt/tomcat/bin/`*) and add the following into the directory

```bash
#! /bin/sh
export CATALINA_OPTS="$CATALINA_OPTS -javaagent:/usr/local/bin/jmx_prometheus_javaagent-1.1.0.jar=9404:/etc/opsverse/exporters/jmx/config.yaml"
```

:::hint{type="success"}
Ensure the file is executable using the command `chmod +x setenv.sh`
:::

Restart Tomcat and in a few seconds you should start seeing Tomcat metrics in the Metrics Explorer in your ObserveNow Grafana

# Logs

## Configure Observe Agent

To pull Apache Tomcat logs into ObserveNow, you only need to add a new block to the agent config. Open up `/etc/opsverse/agent-config.yaml` and under `logs -> configs -> scrape_ configs` add the following block:

```yaml
- job_name: tomcat
  static_configs:
    - labels:
        job: tomcat
        host: <hostname> # Add unique hostname
        __path__: /opt/tomcat/logs/* # This path may be different depending on how Tomcat was installed
```

## Restart Observe Agent

Restart Observe Agent with `sudo systemctl restart opsverse-agent` and you should see logs in your ObserveNow Grafana under the `Logs` datasource with the label `job = tomcat`