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# JMX Tool

Java VisualVM is a tool that provides a visual interface for viewing detailed information about Java applications while they are running on a Java Virtual Machine (JVM), and for troubleshooting and profiling these applications. 

## Usage

Step1: Fetch IoTDB-sever.

Step2: Edit configuration.

* IoTDB is LOCAL
View `$IOTDB_HOME/conf/jmx.password`, and use default user or add new users here.
If new users are added, remember to edit `$IOTDB_HOME/conf/jmx.access` and add new users' access

* IoTDB is not LOCAL
Edit `$IOTDB_HOME/conf/datanode-env.sh`, and modify config below:
```
JMX_LOCAL="false"
JMX_IP="the_real_iotdb_server_ip"  # Write the actual IoTDB IP address
```
View `$IOTDB_HOME/conf/jmx.password`, and use default user or add new users here.
If new users are added, remember to edit `$IOTDB_HOME/conf/jmx.access` and add new users' access

Step 3: Start IoTDB-server.

Step 4: Use jvisualvm
1. Make sure jdk 8 is installed. For versions later than jdk 8, you need to [download visualvm](https://visualvm.github.io/download.html) 
2. Open jvisualvm
3. Right-click at the left navigation area -> Add JMX connection
<img style="width:100%; max-width:300px; max-height:600px; margin-left:auto; margin-right:auto; display:block;" src="https://alioss.timecho.com/docs/img/github/81464569-725e0200-91f5-11ea-9ff9-49745f4c9ef2.png">

4. Fill in information and log in as below. Remember to check "Do not require SSL connection".
An example is:
Connection：192.168.130.15:31999
Username：iotdb
Password：passw!d
<img style="width:100%; max-width:300px; max-height:600px; margin-left:auto; margin-right:auto; display:block;" src="https://alioss.timecho.com/docs/img/github/81464639-ed271d00-91f5-11ea-91a0-b4fe9cb8204e.png">

