Collect monitoring data from Java applications or Tomcat

Limits

Only Logtail 0.16.48 and later for Linux supports collecting monitoring data from Java applications or Tomcat servers. If you use an earlier version, upgrade it first. For more information, see Install Logtail on a Linux server.

Step 1: Create a Logtail collection configuration

1. Log on to the Simple Log Service console.

2. In the Import Data section, on the Monitoring Data tab, click Java Application Monitoring.

   This example describes how to collect Java application monitoring data. To collect Tomcat monitoring data, click Tomcat Monitoring instead.

3. Select the target Project and MetricStore, and click Next. In the Select Log Space step, select an existing Project and MetricStore, or click Create Now on the right to create new ones, and then click Next.

4. On the Create Machine Group tab:

   • If you have an available machine group, click Use Existing Machine Groups. Select Host scenario and ECS. From the source machine group list, select the target machine group and click > to move it to the applied machine group list. Then, click Next.

   • If no machine groups are available, perform the following steps to create a machine group. In this example, an Elastic Compute Service (ECS) instance is used.

     1. On the ECS Instance tab, in the Manually select instances section, select the target ECS instance and click Create.

        For more information, see Install Logtail on ECS instances.

        Important

        If you want to collect logs from an ECS instance that belongs to a different Alibaba Cloud account than Simple Log Service, a server in a data center, or a server of a third-party cloud service provider, you must manually install Logtail. For more information, see Install Logtail on a Linux server. After you manually install Logtail, you must configure a user identifier for the server. For more information, see Configure a user identifier.

     2. After the installation is complete, click Complete Installation.

     3. On the Create Machine Group page, enter a Name and click Next.

        In Simple Log Service, you can create IP address-based machine groups and custom identifier-based machine groups. For more information, see Create a machine group.

5. Confirm that the machine group is displayed in the Applied Server Groups section and click Next.

   Important

   If you apply a machine group immediately after you create the machine group, the heartbeat status of the machine group may be FAIL. This issue occurs because the machine group is not connected to Simple Log Service. To resolve this issue, you can click Automatic Retry. If the issue persists, see What do I do if no heartbeat connections are detected on Logtail?

6. On the Data Source Settings tab, configure the following parameters.

   Parameter	Description
   Configuration Name	The name for the Logtail data collection configuration.
   Cluster Name	The name for the Tomcat cluster. After you set this parameter, Simple Log Service adds a cluster=<Cluster Name> tag to the Tomcat monitoring data collected through this configuration. Important Ensure that the cluster name is unique. Otherwise, data conflicts may occur.
   Application Name	The name of the application.
   Servers	The Tomcat servers to monitor. The following parameters are included: Address: The address of the Tomcat server. Port: The port number of the Tomcat server. The default value is 7777. You can add information about multiple servers based on your business requirements.
   Custom Tag	Custom key-value tags to add to the collected Tomcat monitoring data. After you set this parameter, Simple Log Service adds these tags to the Tomcat monitoring data collected through this configuration.

Step 2: Configure JavaAgent

-javaagent:/tmp/jolokia-jvm.jar=port=7777,host=0.0.0.0

java -jar /etc/ilogtail/telegraf/javaagent/jolokia-jvm.jar --port 7777 start Process_PID

Jolokia is already attached to PID 752
http://127.0.0.1:7777/jolokia/

curl http://127.0.0.1:7777/jolokia/
# Sample response
{"request":{"type":"version"},"value":{"agent":"1.6.2","protocol":"7.2","config":{"listenForHttpService":"true","maxCollectionSize":"0","authIgnoreCerts":"false","agentId":"30.**.**.186-752-5b091b5d-jvm","debug":"false","agentType":"jvm","policyLocation":"classpath:\/jolokia-access.xml","agentContext":"\/jolokia","serializeException":"false","mimeType":"text\/plain","maxDepth":"15","authMode":"basic","authMatch":"any","discoveryEnabled":"true","streaming":"true","canonicalNaming":"true","historyMaxEntries":"10","allowErrorDetails":"true","allowDnsReverseLookup":"true","realm":"jolokia","includeStackTrace":"true","maxObjects":"0","useRestrictorService":"false","debugMaxEntries":"100"},"info":{"product":"tomcat","vendor":"Apache","version":"8.5.57"}},"timestamp":1602663330,"status":200}⏎

FAQ

How can I check whether Telegraf collects data as expected?

You can check the logs of the /etc/ilogtail/telegraf/telegraf.log file on your server. You can also collect this log file to Log Service and search for the required information.